Any ideas on a repower MCI 7 ? has a 8v92 with Allison 740 trans and I can not keep the thing cool. Has new radiators, extra 24x40x4inch radiator, new fan seals, smaller pulley to make fan go faster, separate trans cooler with own cooling system which then goes back to the original cooler, I am at my wits end. Any help would be appreciated. I know is cost money any idea how much and where to get it done? I am in Cornville AZ 100 miles north of Phoenix.
Thanks
Be cheaper and easier to reduce injector and possibly turbo size. What size are the current injectors. Get a heat gun and verify your gage is accurate. Also misters will help if only overheating on long hills. Do you have 92sized radiators?
Don't know about 92 sized radiators, they are 5 row with dimples and are as big as can be put in a MCI 7. I have extra radiator an misting system. I think the ejectors are 500 I will have to check that out. I also have to check out the radiator.
Thanks
Those may be the standard radiator, and would not be sufficient for an 8V92. Pretty sure that bus didn't come with that engine.
You can put bigger one's in, but you'll probably need to modify the firewall. I had to do this on my MC9. Photos in my bus site.
Make sure you have all seals around the radiators tight, and that your blower door seal is tight. The door seal alone can defeat the whole cooling system. Air has to flow through the radiator, not around it. Those two items are the most critical.
Also, as indicated in a previous comment, make sure your gauge is accurate. Install a gauge in the rear, or get some thermistors or other means to record actual temperature.
500 is not an injector size. On a 92 series it would be a 9A90 or 9G85 or similar. Want to reduce your over heating? Don't use the power. Let the bus slow down and down shift when going over a hill. Or if you can't control yourself with the gas pedal, reduce the injectors to 9G75. That will put you at about what a 6V-92 would put out. Good Luck, TomC
It's not the 8v92's fault, even tho they are notoriously hard to cool. My 8v92 in my 102C3 has 8 tube rads. Your rads can't even hope to keep up. I've never overheated my 8v92 even when the temp was triple digits and I was climbing. Granted I have two new radiators, new blower fans new mitre box and very tightly rebuilt and sealed blower box. But you're never ever going to keep an 8v92 cool with 5 tube rads. No way.
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If you go to the tune up section in the 8V-92 service manuals, they list the specs for the various states of tune with injector size,injector setting, delay setting,turbo size and model, boost pressure for different years of mfg. I have a 92 brochure that lists 400 and 450 hp that uses same 9g90 injectors and different turbo numbers. Injectors are most likely set with different pin also. Unfortunately I haven't seen heat rejection numbers except one brochure I have that lists it for a 400hp 8V-71.
The 9A90 was used by MCI they can go from 335 to 435 hp in a 8v92 I came across a lot of MCI 9 that were 8v92TA that only were 350 hp but were 1250 ft lbs of torque MCI also had 8v92 N/A engines they weren't much
Thanks for all the suggestions. AS I have already done the radiators, extra radiators, trans cooler, new seals on blowers and door, misters and drive like I have eggs under my foot where to next?
Since Geoff rebuilt your engine Ed he should know what the injectors are and hp rating is could be it's 475 hp.The MCI 7 combo with the 8V92 and the 1 side radiator don't seem to have the cooling problem,then it could be your engine has the large M injectors and it's just to much for the cooling
You know down here in Texas in summer and pulling a ford F150 supercrew around I have to watch it as it will climb to around 200 when you're climbing hills and running a little faster than normal.Guess you have to watch it on all of them.
Just a thought. Is it possible your water pump is not pumping properly, or maybe there's a blockage in the thermostats or something? You could try removing the t-stats and see if it improves any.
Pull a valve cover and check the tag on the injector.
We have the MC7 combo with the side radiator. We are running 450HP 8V92T. I have not been out west in triple digits to test it but so far so good for us. I am installing a new digital temp gauge on each bank because you guys have all scared me to death about overheating it. We are newbies and learned on this forum how to drive it to keep it cool. I don't know how many tubes our radiator is, guess I'm going to have to check that out.
Which digital gauges are you using?
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When I first bought my 1980 Kenworth K100C 86" Aerodyne (151" wheelbase to pull 45ft trailer inside 55ft length limit back then), I ordered it with the 8V-92TA set at 365hp at 1950rpm-commonly called a "Fuel Squeezer". It was accomplished with shims in the mechanical governor. But it still put out the 1250lb/ft torque with the 9A90 injectors.
Later on, I had it opened up to the full 435hp, and it did make a big difference in performance. Hence-with lower horsepower comes less cooling issues. Good Luck, TomC
PLUS they last longer.Engine and ring life is directly related to load/fuel demand. That is stated in one of the GM service manuals.
Scott
We are using the GlowShift LED gauges. Found them on Amazon. Don't have much of a review yet, I've got the sensors installed but not wired to the gauges yet.
Bruce
I used glowshift gauges for turbo boost, ex. temp, converter out temp, and tranny pan temp. The only ones still working are the temp gauges. The boost sender quit the first trip, The ex. temp never worked. They replaced the boost sensor but it was the wrong pressure. after several calls I GAVE UP. Have at it- buyer beware olebusman
If you have an electronic engine the best way to go for info is with a silverleaf unit. Not the least in cost but it replaces all the dash. Best dollar you can spend on your coach.
Jack
Ed,there is a new C-9 Cat engine on Government Liquidators out for bid and is located in Texas
He better figure the total cost before doing an engine repower. It's those "small" items that get costly.And he better really love that conversion before dumping the bucks into it.
C-9 is a good engine if it doesn't have all the ACERT crap. Good Luck, TomC
Quote from: blue_goose on June 14, 2016, 08:18:18 AM
If you have an electronic engine the best way to go for info is with a silverleaf unit. Not the least in cost but it replaces all the dash. Best dollar you can spend on your coach.
Jack
Is the Silverleaf compatible with the series 50 Detroit with an Allison transmission?
Yep it is made for electronic engines you can buy software and run it on a tablet or lap top too
I have a series 50 in a MCI 102C3. Picture of my dash
Jack
Thanks Blue_Goose. I may have to get the software and run it on my tablet.
It would have to be cheaper to properly address the cooling issues than to consider an entire new re power? Even with all the suggested enlargements and upgrades, that must still be cheaper than a whole new ball of worms doing a complete re power ... along with also addressing THOSE cooling needs?
What exactly do you have now? What specific kind of turbo inter cooling? Any way to improve that? What kind of present tranny cooling? Can you improve that? How bad is your present cooling situation? Was it always like that? Or was it something that crept up over time, hours and mileage?
Cooling can be serious engineering concerns and can have dead high end limitations. We found that out with our old Crown Supercoach ex schoolie. 400 to 450 hp continuous was about it. Side mounted radiator. Big re powers used two side radiators. There must be a way to cool your big Detroit.
Steve think the software only runs on PC's, not apples
Quote from: digesterman on June 16, 2016, 04:04:58 PM
Steve think the software only runs on PC's, not apples
It will run on a Windows based tablet
Quote from: digesterman on June 16, 2016, 04:04:58 PM
Steve think the software only runs on PC's, not apples
That is correct. I have a windows tablet.
Quote from: steve.barnett71 on June 17, 2016, 04:33:37 AM
That is correct. I have a windows tablet.
Silverleaf is not your only option,check with local truck wrecking yards they use the Pro/Driver made by Detroit Diesel only draw back is the screen is small.I have a Pro/Driver I may list in the sale section here later