Today not too far from home on the way back from a one week road trip, my HT740 started slipping in torque converter mode. It heats up too. It still shifts fine. It works fine in lock up. The oil is up where it should be. No leaks.
I am going to drain the oil and drop the pan. From there on, I don't know what I am looking at. Isn't there a filter there? What else should I be looking for?
I see I am going to learn about the HT740, lol.
I am hoping it is fixable with it on the bus. Taking it out doesn't look like fun...
JC
JC
Give us your update on the terrible Bus crash on the
Athabaska icefield. {ex Brewster coach} 3 lost lives, many
extreme injuries.
Wreckage removal in progress, That was a large unit to roll
over down the hill.
Regards Bob
OFF TOPIC SHORT RANT.I am thick skinned and don't give a damn about being PC. Can we get rid of the big ugly thump in a reply like the on above. Not a good look
RANT OVER
Wayne
Bob, how have you been? Re the icefield crash, I don't know anything other than what is in the news.
JC
Guys, I am really looking for advice on my transmission. Thanks.
JC
I heard the Ice Field roll over was caused by a land slide. Not even a full track would deal with that. Now lets get back to JC's transmission!
May have a broken spring in the valve body check all your pressures at the front and rear and pull the governer check to be sure all the plastic is still intact lol maybe start a new topic
Thanks Clifford. I have an Allison service manual for it. 328 pages! I have some studying to do...
So far I am assuming that my shift sequence is: 1C-2C-2L-3L-4L. I'll have to confirm that from the serial number.
Thinking back at the symptoms: it works normally from a stop in 1 and 2, then slips beyond that. So I am thinking that it is the lock up that doesn't work.
Lots to learn... I have rebuilt many engines of all types, but never been into any transmission...
JC
https://www.scribd.com/document/326083921/HT-700-Hydr-Service-Manual-SM1270-199904?fbclid=IwAR18deuZNCVhmer4AixMKPpCJHKMraX5GkUsR5SMcOrRmCyP5urXnUaaDFQ
This is the service manual I have. Might be useful for someone else.
JC
Quote from: lostagain on July 22, 2020, 09:37:22 AM
Thanks Clifford. I have an Allison service manual for it. 328 pages! I have some studying to do...
So far I am assuming that my shift sequence is: 1C-2C-2L-3L-4L. I'll have to confirm that from the serial number.
Thinking back at the symptoms: it works normally from a stop in 1 and 2, then slips beyond that. So I am thinking that it is the lock up that doesn't work.
Lots to learn... I have rebuilt many engines of all types, but never been into any transmission...
JC
no
Quote from: lostagain on July 22, 2020, 07:01:36 AM
Guys, I am really looking for advice on my transmission. Thanks.
JC
If you do it I have the snap ring tool I can ship you it is a bitch without it,when you get into the lock up stator there thin brass clutch parts that break it is easier to buy a rebuilt stator than worry with
I drained the oil: looks good. Dropped the pan. Took the governor out: looks good. The plastic gear looks good. Everything so far looks clean. Now I am studying the manual... I'll take the valve bodies out tomorrow.
JC
The model no is: 740D 7D30. Serial: 17352.
ck modulator on side for leak. Had to change mine once on 740=you could actually hear bubbling in pan. Just put shop air to it in a cup of oil. no bubbles=ok.
Quote from: lostagain on July 22, 2020, 05:27:38 PM
I drained the oil: looks good. Dropped the pan. Took the governor out: looks good. The plastic gear looks good. Everything so far looks clean. Now I am studying the manual... I'll take the valve bodies out tomorrow.
JC
Hows the filter?
The filter has some metal shavings on it. Not a whole lot, but noticeably some. Is that bad?
I started removing the valve body cover plates (heavy suckers when you're working upside down!). Looking at the manual, I am thinking that I am in over my head. And what if I fix something, there might be something else wrong deeper in there. And I don't know how old it is. It came with the bus. I think I remember the previous owner saying he got it used.
I can get a rebuilt HT740 (Coachguard), never installed, for a good price, not far from home.
I would have to pull the engine to swap it out. But that doesn't scare me. Been there, done that...
I am talking myself into doing that...
JC
I would just replace the trans. I have a contact here in Maryland that knows the HT740 like the back of his hand. But honestly for the price of one, I'd just swap them out. Not hard to do. I also have been there done that.
The wafers probably broke in the lockup,the 740 Allison are simple if you have all the special tools and the Coach Guard is a Allison factory rebuild for MCi if the price is right go for it
I am going to start pulling the engine/trans today, to swap with the rebuilt Coach Guard. Maybe later I can look into my broken one when it is on the bench, er... floor. Doing it in frame, upside down, with oil dripping on me, was no fun. Plus, like I said, it is beyond my abilities. Plus, once the engine is out, I can tidy up and clean up in the bay, and paint the engine. Then I can leave the doors open at bus rallies, ha ha!
Rattle can rebuild?
Good choice, leave transmission testing and re-building to the folks who do it every day.
Happy coaching!
Buswarrior
You may even see other items that need attention that you could not see with the engine in frame..>>>Dan
Have you pulled the engine before? i can post a pic of the frame i made for mine.
I would like to see it. I have to pull my motor to change a clutch when i save up for one. Darn expensive. Thanks Raymond
I am half way through disconnecting coolant hoses, wires, etc. I have a dolly/frame thing I built when I pulled the engine out of my Courier 96, thanks. I just have to put bigger and stronger caster wheels on it. They were marginal for the 4-71.
Not much to show but, it works. I block up the rear of the bus to match and just tie frame to bus. Use a come along and slid motor and trans on to frame then lift off to move. Set motor on frame and come along back in to bus.
JC sorry I am not closer or I be there with you helping. Because I know about the same on auto- Tranny's as you. LOL So I will just send positive energy to you. Did it help ?..... :)
Thanks Dave. I need all the moral support I can get...
So I am going to go get this Coach Guard rebuilt transmission. It has been sitting for a few years. Inside, the seller assures me. A thought came to me in the middle of the night: I should have it dynoed, to make sure it is good before I install it. Is that a good idea? I would hate to install it, and find out on the first test drive that it is no good. It is so much work installing it, it seems like a few hundred dollars for a bench test would be worthwhile, no?
JC
Absolutely, if funds and the geography of the test centre make it practical.
Gambling costs too?
Happy coaching!
Buswarrior
You could also make the sale dependent on the test results..>>>Dan :^
Does the seller have documentation from the re-builder, and are there appropriate ID plates and tags on it? Is it totally clean or painted? If it is a unused rebuilt with a guarantee (probably now expired), it might not need dyno testing, if everything is above board.
The seller in this case would make the deal good if there was a problem I know him ,the dyno test is not going to cheap,If it wasn't for the freight both ways Penske would have been a better deal
It has a Coach Guard ID plate on it. I hear they would've sent it to Allison's for the rebuild. It is painted, never been installed on anything.
The seller is a long time bus nut and member on the BNO board, joemc7ab. He is near Edmonton, 3 hrs from me. I think I can trust him. He got the transmission from the Edmonton Greyhound shop.
All the Coach Guard Allison's I have installed were rebuilt by Allison,with a face like Joe what not to trust he is a good guy I knew him for a long time,I think I would forget about the Dyno some places charge you $1500.00 to Dyno a 740
Allied Transmission quoted me $1000 to dyno. Thanks but no thanks... I drove up to Joe's yesterday. Great visit! The transmission looks good. We toured his 1990 Prevost Country Coach. Beautiful! I also brought home his frame on wheels to pull my engine onto. I'll return it later. Today I am hoping to pull the engine. Everything is disconnected: lots of work...
Quote from: lostagain on July 29, 2020, 07:41:56 AM
Allied Transmission quoted me $1000 to dyno. Thanks but no thanks... I drove up to Joe's yesterday. Great visit! The transmission looks good. We toured his 1990 Prevost Country Coach. Beautiful! I also brought home his frame on wheels to pull my engine onto. I'll return it later. Today I am hoping to pull the engine. Everything is disconnected: lots of work...
1000 bucks is cheaper than here Penske sent me a bill for $1500.00 lol 5 years ago it was $300 to dyno and set the shift points on a 740 damn Cov-19 virus
I think I visited Joe about 18 yrs ago passing through Edmonton , but he was selling his Prevost? He had a big insulated building if I recall
Quote from: niles500 on July 29, 2020, 03:57:40 PM
I think I visited Joe about 18 yrs ago passing through Edmonton , but he was selling his Prevost? He had a big insulated building if I recall
I don't believe Joe has owned his Country Coach Prevost that long maybe 10 years now
He has an old MC7 with plywood over the windows and tarps over the roof. Also an old Prevost (1980s maybe) in the trees and weeds. The newer Country Coach is in a nice insulated shop. He was a house builder, so his house and outbuildings look nice and professional.
JC
Quote from: lostagain on July 29, 2020, 07:07:46 PM
He has an old MC7 with plywood over the windows and tarps over the roof. Also an old Prevost (1980s maybe) in the trees and weeds. The newer Country Coach is in a nice insulated shop. He was a house builder, so his house and outbuildings look nice and professional.
JC
That's a Dutchman for ya! ;D
Quote from: Van on July 30, 2020, 06:30:30 PM
That's a Dutchman for ya! ;D
LOL yea he has washer drier combo unit that has never been used except to store wine going back to Canada
Quote from: luvrbus on July 30, 2020, 06:35:41 PM
LOL yea he has washer drier combo unit that has never been used except to store wine going back to Canada
He always gets through the border clean!
Last time we came through the border from Alaska they seized the fresh cut moose antlers I didn't declare. :(
They're probably hanging over a desk somewhere...
About 10 years ago I was pulling my engine and trans to replace the 4 speed with an MT654 auto.
While I was in the engine bay, I replaced every hose there....fuel, coolant, air, didn't matter. Way easier to do it without an engine in the way.
Best of luck with the repair, JC.
Mark
Thanks Mark. I am going to do that too. And clean up and paint. I was at Wajax the Detroit Allison dealer in Calgary yesterday for oil and trans fluid filters. I bought some cans of Detroit silver series paint. I have to remove the alternator, PS pump and air compressor for easier access. I've had an annoying minor oil leak at the back. I suspect it is from the compressor. I'll look into that.
Big job...
I'm glad you picked the Silver paint. Apparently, if you paint a stone with Detroit Diesel green, it will leak oil.......
Following your thread with interest. Likely won't see you south this year. I think we are headed west to BC instead.
Mark
JC somewhere in my pile of papers I have service bulletin that Allison requires a filter on the return line so check with the dealer about adding another filter,I do know United or Penske will not warranty their rebuilds without adding another a filter on the return or suction making it a 2 filter system
A couple of years ago, I installed a filter on the line between the converter and the shell cooler that is on the side of the engine. Would it be better in the return line? I thought being on the out line, it would take a bit of heat off before it got to the cooler. Of course, I still have the regular filter on the other side too.
Interestingly, when I limped it home with it slipping, the trans temp went up to 220F from a normal of 180, 190F. But the engine temp stayed normal at 190F. It was fairly warm outside. So I guess the engine temp is not as affected by the transmission as I thought.
Quote from: lostagain on August 01, 2020, 08:19:30 AM
A couple of years ago, I installed a filter on the line between the converter and the shell cooler that is on the side of the engine. Would it be better in the return line? I thought being on the out line, it would take a bit of heat off before it got to the cooler. Of course, I still have the regular filter on the other side too.
Interestingly, when I limped it home with it slipping, the trans temp went up to 220F from a normal of 180, 190F. But the engine temp stayed normal at 190F. It was fairly warm outside. So I guess the engine temp is not as affected by the transmission as I thought.
There is lot of hype about how much heat the Allision affects the engine temps the plate cooler does a damn good job
a slipping transmission will make more heat. it's a vicious circle.
JC I am glad you are making use of Joe's transmission. It certainly looked good in his shop. Along with its history.
At one time I was thinking of installing a automatic in my 5B I was considering buying that 6V92 he also has in his shop, and the tranny you bought and install them at the same time.
But things changed and I learned to downshift properly LOL.
Hi JC, I thought you might like this photo, from BC. A guy named Simmons, on facebook...
Tom, I think this photo is in the West Kootenays of BC. Very mountainous with lots of lakes.
I am slowly making progress on my project. The trans is off the engine. I took the flex plate off the crank shaft and removed the rear seal that looked like it was starting to weep a little. Tomorrow I will get a new seal at the DD Allison dealer. Then the rebuilding process begins... I refer to the service manual a lot, and have been on the phone with Clifford almost every day for advice. I am lucky that I can do this at home in my shop. I shudder to think about the hassle of the transmission failing far from home...
Quote from: lvmci on August 03, 2020, 06:02:24 PM
Hi JC, I thought you might like this photo, from BC. A guy named Simmons, on facebook...
LOVE THAT PHOTO! :^
Over the hump now!
The sleeve and rear seal were almost $300 at the Detroit dealer, gulp... Installed them yesterday, put the flex plate back on. I took the pan off the rebuilt transmission of Joe's. Looks good. Lots of fresh looking ATF left in there I am assuming from Dynoing it after the rebuild. Drained as much off as I could. Will refill with 15W40. Re installed it onto the back of the engine. The motor mounts that hold the tranny to the cradle make it difficult. Then you have to align the bolt holes to the bell housing, then align the flex plate to ring gear bolt holes, etc. Today will reinstall the compressor, PS pump. Made some new gaskets. And the alternator (belt driven). Then there will be another day to finish tidying up the engine bay before I push the engine back in. Then another couple of days to reconnect all the wires and coolant lines, and turbo and exhaust and intake plumbing. Oh and I want to move the EGT probe from after the turbo to upstream of it on the manifold Y. Lots to do...
Looks like your rocking and rolling right along JC..>>>Dan
Wow! Parts are plenty ex$pen$ive!
Glad you are getting to the good part, where it all starts coming together. It is a GOOD feeling.
I've never though of using 15W40 in my trans. I have Dexron3 in it right now, and had considered using 30W. Prewarming prior to use may be an issue here in our climate.
Following with interest!!
Mark
Look at the Allison literature. 15W40 C4 is one of the approved fluids for the 700 series. I find it shifts smoother, and runs a little cooler maybe. Starting on a cold morning, I preheat the engine. You could idle for a few minutes to warm up the trans before moving.
I'm about due for a fluid change in the trans. I'll check the Allison recommendations first..I have several pails of 30w, and I think a couple of pails of Dex3 here already.
The Dex3 seems to work well in my MT654, and shifts well.
We won't be seeing you in AZ this winter. Perhaps next year, if things improve.
Mark
Quote from: lostagain on August 08, 2020, 08:19:29 AM
Over the hump now!
The sleeve and rear seal were almost $300 at the Detroit dealer, gulp... Installed them yesterday, put the flex plate back on. I took the pan off the rebuilt transmission of Joe's. Looks good. Lots of fresh looking ATF left in there I am assuming from Dynoing it after the rebuild. Drained as much off as I could. Will refill with 15W40. Re installed it onto the back of the engine. The motor mounts that hold the tranny to the cradle make it difficult. Then you have to align the bolt holes to the bell housing, then align the flex plate to ring gear bolt holes, etc. Today will reinstall the compressor, PS pump. Made some new gaskets. And the alternator (belt driven). Then there will be another day to finish tidying up the engine bay before I push the engine back in. Then another couple of days to reconnect all the wires and coolant lines, and turbo and exhaust and intake plumbing. Oh and I want to move the EGT probe from after the turbo to upstream of it on the manifold Y. Lots to do...
300 I hope that was Canadian,a good one from DD are around $120 to $150 here the after market crap is a lot cheaper around 80 bucks for the set
Nice JC, yep me too Mark I use Dex 3 in my MT654.
Quote from: lostagain on August 08, 2020, 08:38:39 AM
Look at the Allison literature. 15W40 C4 is one of the approved fluids for the 700 series.
That used to be true, but Allison dropped recommending oil and Dexron fluids with Service Tip #1099 (June 2018). They recommend approved TES 295 fluids (not just Transyd) for all series including HT700. I realize Cliff says HT740's love having oil in them, and it was used for severe service duty for years in vehicles like garbage trucks, but the Allison Engineers have revised their thinking even though the HT740 is considered obsolete.
When I switched to TES 295 when in Florida. I could not believe the difference how the V730 performed.
I had a real good comparison as I drove down there with Dexron 3 came back with Transynds version of TES 295.
Made me a believer, even though i took a loan out to pay for the TES 295. :0
Quote from: DoubleEagle on August 09, 2020, 10:24:45 AM
That used to be true, but Allison dropped recommending oil and Dexron fluids with Service Tip #1099 (June 2018). They recommend approved TES 295 fluids (not just Transyd) for all series including HT700. I realize Cliff says HT740's love having oil in them, and it was used for severe service duty for years in vehicles like garbage trucks, but the Allison Engineers have revised their thinking even though the HT740 is considered obsolete.
Now Walter read all of it starting with the beginning serial number that applies to that service tip 251023350088 was the 1st 740 to have the new lining material for the 295 spec,One thing good about systemics it stands more heat and less fluid changes if you have retarder transmission, the B500 was living proof 295 did not extend the life of those
My new transmission is a MCI Coach Guard rebuid. Serial no: 30-29833. Is 15W40 OK in it?
Quote from: lostagain on August 09, 2020, 11:54:34 AM
My new transmission is a MCI Coach Guard rebuid. Serial no: 30-29833. Is 15W40 OK in it?
You would be fine with that 29833 number,you can have the fluid that it was dynoed with tested most on a dyno are tested with a synthetic same color as the Dexron they use one type oil for all B500 or the MT 640 makes no difference,I had my Allison 4060 serviced at Williams and thought I lost a family member almost a 100 bucks a gal for Transynd Transmax Allison spec 353 not the 295 spec because my hyd fan runs off a pto on the Allison
So what oil does the B500 use?
Quote from: Jim Blackwood on August 09, 2020, 01:04:19 PM
So what oil does the B500 use?
Transynd is preferred now but back in the mid 90's till around 2002 they used Dexron,C-4 engine oil.or Transynd what ever the operator chose cost wise that worked for him
Quote from: luvrbus on August 09, 2020, 10:55:48 AM
Now Walter read all of it starting with the beginning serial number that applies to that service tip 251023350088 was the 1st 740 to have the new lining material for the 295 spec
You might have a different version or a more complete bulletin, the 28 page Service Tip I have is 1099, Rev U, dated June 2018, and I don't see any indication of beginning serial numbers. I sure would not use $100 a gallon Transynd in an old 700 series, but I would consider Mobil Delvac 1 at $33.99 (Summit Racing in Ohio). ;)
Quote from: DoubleEagle on August 09, 2020, 01:42:50 PM
You might have a different version or a more complete bulletin, the 28 page Service Tip I have is 1099, Rev U, dated June 2018, and I don't see any indication of beginning serial numbers. I sure would not use $100 a gallon Transynd in an old 700 series, but I would consider Mobil Delvac 1 at $33.99 (Summit Racing in Ohio). ;)
Walter 1099 came out in 2002 they revise and retract it weekly ,read it close it's a recommendation,since Allison no longer supports the 700,or 600 series and hasn't in over ten years they change specs,me I never heard of the 353 spec except for off highway use.Williams used the 353 spec was supposed to be latest spec for my 4060 with the PTO driven hyd pump.
Walter I fell into the Transynd trap with my FS 740 Allison back in 1999 ,I changed over from Dexron because of the hype on these boards one day I shifted into gear from being parked at a Eagle rally and nothing happen.I called Bob Ware a Allison guru in Ca asking for help the 1st thing he asked did you change over Transynd I said yes he told me that is the problem the clutch lining feel off sure enough when they pulled the pan the linings were in the pan from then on I been leery about changing fluids in the older transmission,lol by the way the Transynd was almost a 100 bucks a gal in 1999 the prices have dropped a lot in the past 20 years
My local oil man has a terrible opinion on synthetic so we're rolling with dextron 111 in the b500. I expect to get at least another 50000 miles out of this tranny, which currently has an estimated 450,000. Clifford did say some last till 600,000, so we're taking the chance I guess. 8) 8)
I mean Allison said it was ok for the first 15 years and the tranny sure didn't change...
So then, it looks like oil or Dexron III are what is safest for older 740's. My last Eagle was purchased from a Allison re-builder, and they serviced it with Dexron III. I asked whether TES 295 was an option, but they said it came with Dexron III, and they were sticking with it. Now there will be a few people wondering what to do with their particular Allison. This important detail of changing the lining material to be compatible with Transynd should be spelled out a bit better even though they no longer support the 700 series. I remember them announcing in 2002 that they were testing Transynd in various series, but I never saw the results. Looks like your trans was an early result. Thanks for straightening this out Cliff.
So I will fill mine with 15W40. It worked good in my other 740...
You have to weigh the cost option is Transynd worth the price no more miles than the average person drives his bus a year ,when William did mine Tranysnd was the new best thing since sliced bread, they done it twice for 800 bucks a pop to make sure all the old fluid was out,I was told it would run cooler and it did about 3 degrees and my FS 740 with the Bennett shifter shifted so smooth I never could never tell the difference with Transynd.My hyd fan holds 20 gals and I thought about switching and asked the manufacture and he said in no uncertain words stick with the Dexron lll that it came with so I will
in late 2016 I changed the Allison 4000 fluid and the 2006 filters ? with this stuff
https://lubricants.petro-canada.com/en-us/brand/duratran-xl-synthetic-blend
and at the time it was rated for the tes 295
this spring I had to replace some o rings in 2 of the lines and at that time I changed the fluid and filters again with the same duratran fluid as it is not that much $$$ at about $ 105 for 5 gal. pail so when I buy 3 pails the price is not that bad
any one else using this ?
thanks dave
On my trip to Blytheville last year I lost the return hose from the transmission cooler to the sump of the v730.
In replacing the hose and the leaking I lost about a gallon of oil. Not having the manual with me so looking at the remaining oil i just replaced it with 10w30 rotella.
After I got home ever one on the boars gave me a hart time. they said to use transend.
I finally found in the manual that came with the v730 and it said to use 10 weight mineral oil.
Had worked for 25 years so i figure it is good enough now.
uncle ned
Finally finished reconnecting everything. Takes a lot of time. Lots of details to take care of. Took it out for a test drive. Works great! I think it shifts smoother than the old one. Only a couple of things don't work: the cruise control (odd because it is an air operated Bendix that is all up front in the spare tire compartment and is not related to taking the engine out). Will have to look into it. And the pyrometer doesn't work. All I did was take the probe out and put it back in... Will look into that too. But otherwise all good. Also thanks to Joe for letting me use his gurney/cart/ cradle (whatever it is called) to pull my engine onto. Well built, solid and plenty big enough and just the right size. I pulled the engine with a chain come-along, and pushed it back in with my skid steer. That part is easy with the right tools. It is the disconnecting and reconnecting all the wiring and coolant and hydraulic lines that takes all the time. And the fixing and improving things as you find them...
Anyway, done. Yea!
Good job JC now you are dressed for the party and no party to go to
LOL Clifford! The weather is nice here now. But I have to work the harvest the next six weeks driving grain trucks, so no going with the bus anyway. And it doesn't look like the border is reopening soon, so we might not be coming South this winter. Oh well, I'll have lots of time in the shop...
Quote from: lostagain on August 16, 2020, 07:20:57 PM
LOL Clifford! The weather is nice here now. But I have to work the harvest the next six weeks driving grain trucks, so no going with the bus anyway. And it doesn't look like the border is reopening soon, so we might not be coming South this winter. Oh well, I'll have lots of time in the shop...
If you toss the old 740 I will buy the oil pan from you ok
OK. I will ask the transmission shops if they'll give me any money for it. If not, it'll go in my scrap pile.
The moral of the story is:
1: HT740 transmissions aren't bullet proof, as is the myth believed by many bus nuts. They are very robust, but wear out and break in time, like anything mechanical.
2: I am so lucky that I wasn't stranded a long way from home when it broke. It would've been $10 to 20G to have it fixed on the road. It would've happened half way to Florida, as this is where we wanted to go to help our son move. We didn't go because of Covid border closure.
3: it was a big job. Good thing I had the time.
Glad it worked out for you as far as a convenient breakdown...
We know all too well what it's like breaking down far from home...
We're never really alone as there's always this & other support groups that have a way of lightening the load. :)