Alarmstat probably saved the bus

[bcaddel]

We just spent two weeks on the Delta in California and had a great time fishing with the kids and grandkids. We were headed back to Reno Nevada and just as we were coming into Sacramento when all Hell broke loose. I had scanned my instrument panel only moments previously and noticed the temp gauge was around 195 and thought it was running a little warm and noted I would need monitor that closely since it was around 100 degrees outside and we had some mountains to go over.

I just recently purchase 2 new alarmstats (I thought my old ones might not be working) but hadn't installed them because I was a little uncomfortable about the automatic shut down feature and not wanting the bus to shut down in an inappropriate location. Just a few moments later I looked at the temp gauge and it was moving up pretty fast to the hot side and before I could say Holy S***, the alarm went off, the Low Oil light came on, the hot engine light came on and by the time I read the warning lights the engine shut down. I was rattled to say the least, and luckily there was a bicycle lane on my right and I coasted into it (more than filled it up) and started thinking my engine is probably shot. The temp gauge kept rising and got to 220 or maybe just a little bit more.

I went to the engine compartment expecting to see Oil everywhere (the low oil light had came on) and everything seemed to be OK except for the temp gauge back there read 220 also. There wasn't any fluid below the bus and no oil on the boat I was towing. I checked the oil and it seemed very thin but full. I then started looking around the engine and finally saw a couple of drops of liquid dripping from the back of the engine. The hose providing water to cool the air compressor seemed to be the culprit and when I moved it it pretty much broke off in my hand and the rest of the water came out of the system.

This was last Sunday afternoon and I didn't expect to find any hose to replace the broken one, but I went ahead and removed the broken one and noticed the fittings were the same type we used on airplanes (I used to be a Aircraft Mechanic 30 years ago) so I took the fittings off the hose and decided to go looking around. I ended up at a Lowe's (5 blocks away) and found what they called a "High Pressure" hose for a pressure washer that was just a little bigger than the end of the fittings on my current hose. I bought some Teflon tape to wrap around the fittings to take up the space and some clamps and the hose and headed back to the bus.

I put it all together and installed it on the bus, filled it with water and started it up. Everything looked good, Oil Pressure was good and I was planning to just drive it to a parking lot to get it off the street. After I got in the parking lot and it was holding up and the temp came up to 180 with no apparent leaks, I couldn't resist driving it a few more miles to see how it held up.

Well, the bottom line is we made it all the way to Reno (150 miles) and the radiator is still full and them temperature of the engine ran perfect and did not heat up any. I really thought I had done some damage but the Alarmstat shutting me down most likely saved my bacon because I would not have pulled over where I was but would have drove several blocks further to a parking lot to be out of traffic but that would have probably fried the engine since it got up to 220 as it was I surely would have gone over that temp had I drove it any further.

I guess Luck is better than skill anyway you slice it..

[Melbo]

Sweet deal

When I had my 71 it would overheat and shut down in the mountains all the time

Let her cool down and away you could go until it got hot the next time

Melbo

[Chopper Scott]

I'm not for sure what bus you have but my MCI 7 has a feature that when the motor is running you can bypass the shutdown temproarily by pusking the start button and holding it in. It allows you to move to a safer spot. One should check to make sure the starter isn't engaging in case someone has bypassed the fuel pressure switch that allows it to do so.

[bcaddel]

I have checked and my starter does engage when the motor is running. I have to flip the switch to turn the step light ON for the starter to engage so I think I will start turning that switch back off once I start the engine each time, that way I could try and see if pushing the start button keeps it running if it ever shuts down again. (it is a 1971 model year mc7)

It all happened within 5 to 10 seconds so I might not be a fast enough thinker to remember the start button trick. I just had a new water hose made up at the local Petro, and purchased 4 feet of additional hose. I need to reread the "Items to Carry" in the coach list and start accumulating more of them so I am a little more prepared for the next emergency.

[Iceni John]

Bob,
I definetely need to replace both my air compressor coolant hoses as well  -  they are really crusty looking (but they don't feel too soft).   I have a Bendix Tu-Flo 750 direct-driven of the back (front?) of my 6V92.   Do you remember what sizes/lengths/fittings your hoses are?
Like you, I have an alarmstat with all the bells and whistles, but I want to fix potential issues now instead of alongside the road later.
Many thanks, John

[DaveG]

Engine shut-down systems are nice, but also as mentioned it is REALLY NICE to have some type of by-pass for getting off the road and to a safe place.

[bcaddel]

John
Here is the info on the hose I had made up
17" of HTR5-8 100R5 hi temp cotton cover hose (this is a 13/32" hose)
R501 8X6 - NPTF solid male fitting
R509 8X8 - JIC female swivel fitting

A lot of that is Greek to me but I am assuming anyone that sells hoses and fittings would know exactly what it is. My old hose was only about 15" long but some of it is gone so I added 2" to insure it was long enough as I have plenty of room where in connects. I definitely advise replacing your hoses if they look like mine did.

[David Anderson]

I had the same thing happen to me in my Eagle (6v92) about 7 years ago, except it was a hose clamp.  My alamastat was screaming at me and I pulled over, and killed the engine.  I let her cool down for about 45 minutes, took the hose clamp off my toilet drain pipe, filled with water and went on my way.   I've never heard the alamastat again, so I decided to wire it with a relay that engages it when I engage the starter.  That way it lights up every time I start the engine.  That gives me some indication it works.

David

[JohnEd]

Bob,
I definetely need to replace both my air compressor coolant hoses as well  -  they are really crusty looking (but they don't feel too soft).   I have a Bendix Tu-Flo 750 direct-driven of the back (front?) of my 6V92.   Do you remember what sizes/lengths/fittings your hoses are?
Like you, I have an alarmstat with all the bells and whistles, but I want to fix potential issues now instead of alongside the road later.
Many thanks, John

They should be supple when new and get harder as they age.  Hard is bad.

I drove that 200 yards to the safe area and it cost me the engine.

You need an alarm that says things are going to hell and then a shutdown stat that kicks in a few degrees higher.  I am all in favor of the shut down bypass.  I think I would use it less than some on this board but that is OK....t each his own.  You saved yourself 15 to 20 K dollars of being polite and extra "safe". Not joking about that, now.  If I saw 220 on the dial I would have shut down with or without the stat assist.

John

[Hi yo silver]

Excellent thread!  I can't thank you guys enough, who are sharing experiences like this to help the rest of us.  My alarm has gone off briefly a time or two, but no issues thus far. (Knock on Stainless!!)
Dennis

[JohnEd]

I had the same thing happen to me in my Eagle (6v92) about 7 years ago, except it was a hose clamp.  My alamastat was screaming at me and I pulled over, and killed the engine.  I let her cool down for about 45 minutes, took the hose clamp off my toilet drain pipe, filled with water and went on my way.   I've never heard the alamastat again, so I decided to wire it with a relay that engages it when I engage the starter.  That way it lights up every time I start the engine.  That gives me some indication it works.

David

I recently had my cruise control go out on my 85 Ranger.  I got a bum leg(s) so cruise is more important than a nice opyion.  I messed up the switches on the steering wheel trying to get to the circuit board to hm out the switches.  DRAT!  I then went over to my bud at the wrecking yard and he fixed me up with a whole new wheel for $10.  Got caught letting that deal out the door and the $#!% hit the fan......for him.  Got that bad girl home and installed her...cruise light still wouldn't come on....DOUBLE DRAT!  On the freeway a few days later I tried the cruise just for grins and it worked.....grinned broadly.  I later found that the dash panel light had burned out. KURSNIDLEFRIZ!  Went through all that for nothing.

I have a low oil pressure alarm and an over temp alarm and they are the same item.   Also have a rather obnoxious back up alarm mounted under the dash so I don't get tempted to drive very far.  I have to shut the alarms off to start or the oil will trip the system and if I leave it in bypass I get the alarm light without the buzzer to tell me I am explosed...so to speak.

here is just so much money riding on this and we cannot help a fellow Knut with a trashed engine unless our name is Clifford or Don or?  I am no good to them though.  Install and maintain those systems.

John