55 M37 hard starting

dodger · Post by **dodger** » Sun May 04, 2008 8:46 pm

I think its just worn out too, I also suspect #5 is a burnt valve or stuck open. Hopefully not a broken piston! I have a 52 Fargo and while it doesn't start the best its going within 30 seconds so I don't think its entirely operator errors although it might not be helping. Problem is what I think runs decent might be terrible to someone else. It runs fine seems to have a bit of a lean bog when you press the gas to fast but other than that its ok. Seems to be low on power as it dies out going up semi steep hills on the grid roads here but I can see why if its only got 60lbs cylinder pressure. Any sources for rebuild kits? Will a engine from a 49 dodge 2 ton fit?
Thanks again everyone

MSeriesRebuild · Post by **MSeriesRebuild** » Mon May 05, 2008 8:22 am

This is pretty much what I suspected when you mentioned slow cranking, although something doesn't add up. On #5 with a 0 reading, that would be a dead skip, you said it ran decent, not possible with a 0 reading. Most likely is a stuck valve on #5, I doubt seriously this being a head gasket issue at all, if it were a 0 reading on 2 adjacent cylinders would result. Nothing wrong with running the test again with another gauge just to verify, but I think you have your answer, highly likely a total rebuild is in order. Is your truck a Canadian M37? If so it should have a 251 engine. I have a newly rebuilt 251 engine that is 100% complete & ready to install. If this applies & you have interest, sent me an e-mail.

dodger · Post by **dodger** » Mon May 05, 2008 8:48 am

It does have a miss but its not consistent more like spark skip and it only does it sometimes. I did the test on #5 numerous times as I didn't think it was dead either but still nothing. I could do the comp. test again but I think I have my answer now. It is a Canadian built and ex-canadian military version. I'll send you a email right away.

MSeriesRebuild · Post by **MSeriesRebuild** » Mon May 05, 2008 1:36 pm

dodger wrote:It does have a miss but its not consistent more like spark skip and it only does it sometimes. I did the test on #5 numerous times as I didn't think it was dead either but still nothing. I could do the comp. test again but I think I have my answer now. It is a Canadian built and ex-canadian military version. I'll send you a email right away.

I would guess a valve is sticking, then coming loose, sticking again, etc.

powool · Post by **powool** » Mon May 05, 2008 3:57 pm

My engine read 0-0-0-0-0-0 - all exhaust valves stuck slightly open (cold). I had been able to get it started with enormous amounts of starter fluid, which must have created enough of a seal to get it started.

Once running, it ran reasonably well. I carried a load of rock with it up some hills at reasonable speed, for example.

However, I gave up on it and am rebuilding another engine. Life is too short for crazy worn out engines.

knattrass · Post by **knattrass** » Mon May 05, 2008 5:21 pm

Hey Paul - good to hear you are still plugging away at the engine (and family!!). Hope all is well - Keith

dodger · Post by **dodger** » Wed May 28, 2008 9:23 am

Anyone know where I can get a rebuild kit? (bearings, rings and gaskets)
Thanks,
Dodger

Lifer · Post by **Lifer** » Wed May 28, 2008 12:44 pm

All the usual parts houses and MV-specific dealers will have them (or be able to get them). When shopping for a rebuild kit, make sure you tear your engine down first, then mike the cylinders and crank bearing surfaces. You may have to hae some machine work done and then order the parts in the appropriate undersize or oversize as the case may be.

Cylinders can be bored out to .060" oversize, but that's as far as it will go. After that, installing sleeves and standard pistons/rings would be required. Some shops recommending sleeving after .040" overbore, especially if the engine may be expected to see heavy use for an extended period of time.

Crankshaft main bearings and rod journals can either be ground down to specific standard undersizes or built up and reground back to standard bearing size.

Once you've checked everything and made sure the round parts are truly round, then you may order your parts!

Happy wrenchin'!

dwayneski · Post by **dwayneski** » Thu Jan 19, 2012 8:01 am

Before I went any further I would check compression with another gauge. He stated it ran decent after it was started,60 lbs wouldn't run decent. One other thing when starting the choke must be used properly,or you can have starting problems. If you're new to the world of flatheads you'll need tto learn how to start them properly.

My soms truck starts fine in the warm weather but we cannot get it going when it is cold, it is 15 degrees today. DJ what is the proceedure for starting the flat heads?

55 M37 hard starting

Re: 55 M37 hard starting