1976 Cummins 555 diesel starting problem

[Capnted]

My Cummins is getting harder & harder to start, now requiring ether every time. When we were in MN, we blamed it on gelled diesel & half-filled both filters with 911 to get it started. But now that we've made it to sunny FL, the cause has to be in the engine itself.

It runs just as well as always--65-70 mph all day long--and idles perfectly once started. But if we shut it off long enough to get diesel & lunch, it won't restart without a lot of ether.

A mechanic at TA changed the fuel filters once again and cleaned out the fuel/water separator. His theory was that it is losing its prime--that there should be a check valve near the engine and near the tank. He couldn't find any. Anyone know? He didn't think it was the high pressure pump because it runs well. How do I diagnose fuel line leak/bad check valve/lift pump/injector pump--or something else?

Thanks,

Ted

[Richard and Rhonda]

Install a tee fitting and pressure gauge as close to the head as you can get. The gauge should tell you what the fuel pressure is when running and as you are starting to crank. You could have a faulty check valve or a cracked fuel hose that is allowing air in the intake hose. Check the tightness of all fuel line fittings.

[77newell]

The only thing that changed from before the problems started and now seems to be the passage of time. If the fuel supply hose to the engine is leaking air, it will be leaking air all the time and even after the engine is running. If you can temporarily tie a piece of clear tubing on the return line you may be able to see bubbles (there should be absolutely none) especially at idle when fuel flow is low. Alternatively a gauge that can read very slight vacuum installed in the supply line as close as possible to the first fuel pump should show a slight vacuum after the engine is shut down and should remain a slight vacuum if no leaks are present.

If check valves could be the problem they first have to be present and it seems your system has none, unless the mechanic didn't know his check valves from his other fittings.

The problem cannot be a restriction because once started you can go full throttle with no problem.

Let us know what you eventually find or provide more information on what you've tried and what resulted.

Jon
77 Newell with 6V92TA

[Wally Arntzen]

I had a 78 with the same engine and it had a either canister installed with a switch on the dash. Every time I started the engine I had to give it a squirt of either or it would not start. I had the coach for five years and it always worked fine. I sold the coach and the buyer used it as it was for two more years and replaced it with a 8v92. From what I was told at a Cummins dealer they were designed with the either canister.

Do you have the canister or do you squirt the either into the air cleaner.
These engines were great in their time but I have no idea how long the are going last and how many are still around. I hope you solve your problem or you may be looking into another engine preferably an 8v92.

[Capnted]

Yes--i have the ether cannister. I've been through a whole cannister in a month or so. I used to use it only when the temp was cold and the engine was cold. So something has changed--and i know ether's not good for the cylinders & rings.

[Wally Arntzen]

There must be a Cummins dealer sonewhere close to you in Florida that could look at it and give you an idea of the problem.
On my coach I only gave it one squirt to start and a canister would last me a couple of years. I used it a lot and put approximately 30,000 miles a year on it. The Cummins dealer was in Minnesota where you left and he informed me that using it as designed was no problem for that engine but he said to make sure that I did not keep pouring in either if it had a problem starting. I never had a problem starting.
It sounds like you may have something serious and I wish you well on what it may be.

[Capnted]

Headed for garrison, MN. Just bought an '83 Newell in Indiana.

Where in MN do you live?

Ted

[chockwald]

Congratulations Ted! Pictures coming?

[Wally Arntzen]

Ted, I'm currently in Maplewood, Mn, which is on the east side of St Paul. There is a Cummins repair shop in the Twin Cities and I think it is somewhere in Roseville. The moved several years ago but you should be able to find them. Are you visiting at Garrison, its a beautiful area and good fishing if you are fisherman. Have fun and contact me if you need anything that I can help with.

Wally

[Wally Arntzen]

Ted, just a follow-up, I just noticed that you went from a 77 to an 83. I suspect that the 83 has a 6V92 or 8V92 and not the Cummins 555 that you had in the 77. If that's the case congrats on the upgrade and have happy travels.

Wally

[Capnted]

It's a Cummins 903. Guess its not a common engine, but so far it's running great and has three times the power of the 555. Took her to a diesel garage in Brainerd for a full service. No bad news. Got a few things fixed & feel like we got a good coach. Only things not fixed are the Jake brake and the air leveling system. Jake brake has power to the engine so it's internal--decided not to take it further. Leveling system problem is apparently all leaking valves. Not sure i want to go to the expense of replacing them all.

Otherwise, all I can think of is the dash heat & air that doesn't work. Oh, and ordered a converter/charger because the one in it could wake the dead with the buzz it makes. The coach is really clean in & out. We're enjoying the walkaround queen, the remote mirrors, and the overall feeling of "new".

Now, if the price of diesel would goes down, or we learn to make biodiesel in the garage, we'll drive it back to Florida & maybe we can stop & see you on the way down.

Thanks for your interest.

Ted

Garrison, MN

[folivier]

For your leveling valves leaking, maybe pull one and clean or replace the o-ring then see if it still leaks. Had that problem with one of mine. So now I have a new o-ring and a spare solenoid valve.

[Wally Arntzen]

The dash air on those older coaches is really a pain and could be costley to fix. On my 88 I converted it and it still is useless, so I run the generator and the house units to cool the coach which works fine. As far as the air leaks, I changed every check valve, air switch, preasure guage and switches in the coach and mine is lock tight. Did it all with a friend and it was a little expensive.
Good luck with the repairs and do them as you can afford to. Some are necessary for being on the road.

Wally

[prairieschooner]

I agree with Wally, Just run the Generator.
I haven't spent any $$ on my Dash A/C but I have no want to cool off my knees. I figured that I would spend the $$ on diesel before worrying about R12

[HoosierDaddy]

Yeah Capnted. 555 and 903 are visually very similar. On my 555 we found a JBrake wire broken inside the valve cover..Easy fix.

[Capnted]

...for the responses. Will have the valve covers pulled next service & see if the Jake brake is "low lying fruit". Turns out the brakes were WAY out of adjustment so at least I don't have to stand on them anymore. BJ always drags her foot going down long hills anyway. She's worn a hole under the passenger's seat right down to the road. It's not easy riding in that right-hand seat.

Will also try an O ring in the leveler valve. I found replacement MAC air valves for $40 each in Mpls, but while counting them I got to 10, got dizzy & had to sit down. The coach reminds me of a slow-motion camel the way it gradually sits down on its haunches. Good thing is we can get rid of the step after a few days.

Incidentally, we have a switch next to the head of the bed labeled "Compressor". I was afraid to ask what that was for--thought we might find a set of unusual tools in the drawer next to the bed or something. Called Newell service & it turned out that a 110 v. compressor was an option in '83. Ours may have been removed.

Will definitely stop & visit next time in Indiana, Hoosierdaddy. (Best nickname on the forum!)

Ted

[Richard and Rhonda]

Ted,

It may not be your leveling solenoid valves. Check carefully around the ride height control valves for leakage.

Search the forum, some of us have had moderate success with rebuilding the seat in the solenoid valves.