OK the facts. The first 4 cyls were all between 95 and 100 lbs cranking a cold engine. The trouble started in no. 5. It only reached 60 psi and then it slowly dropped to zero!! Next was no. 6 it did the same thing. It pumped up only to about 60 psi and then leaked down and I could hear a hissing as it did. Is this a head gasket or worse?
This all started when I decided to check the plugs which were burning really rich. soft sooty black. Not sure what I should do to reverse that. After I pulled the plugs I took off the aircleaner andI saw oil in the bottom of the intake under it. So one thing led to the next. Sounds like a sick truck to me! HELP please Thanks Rick
rixm37 wrote:OK the facts. The first 4 cyls were all between 95 and 100 lbs cranking a cold engine. The trouble started in no. 5. It only reached 60 psi and then it slowly dropped to zero!! Next was no. 6 it did the same thing. It pumped up only to about 60 psi and then leaked down and I could hear a hissing as it did. Is this a head gasket or worse?
This all started when I decided to check the plugs which were burning really rich. soft sooty black. Not sure what I should do to reverse that. After I pulled the plugs I took off the aircleaner andI saw oil in the bottom of the intake under it. So one thing led to the next. Sounds like a sick truck to me! HELP please Thanks Rick
Pull the head before going further. It may well be the gasket has just begun to fail between cylinders 5 & 6. It is typical for 2 side by side cylinders to act the same with a blown gasket. My guess would be the gasket leak has just started & hasn't fully blown out yet. 95-100 PSI isn't great readings either, but putting off a rebuild will be possible for a while. 100 PSI is as low as one can go & perform decent, I call 100 borderline, below that will be various issues that affect performance, good starting, fuel economy, etc. Let us know what you find when you pull that head. If it's like I suspect & a blow out has started, be sure to check the head & the block deck for flatness before replacing the gasket. There is generally a low spot on a surface where the blow out occured, replacing the gasket without resurfacing to repair the low area will be fruitless.
I wouldn't worry about the liquid in the air cleaner elbow, it's very typical to see that, even on a top notch engine. It comes from a fine mist of oil that is picked up by intake air from the oil bath air cleaner, the bottom of the elbow is where it typically settles out.
[quote= I took off the aircleaner andI saw oil in the bottom of the intake under it. [/quote]
someone correct me if I am wrong, but the stock air cleaner in the M-Series is an oil bath style so there should be oil in there. There's plenty in mine! Apologies if this was NOT the oil you were referring to.
Thankyou Charles.
I will post what I find when the head is removed. I am relieved that some oil in the intake elbow is ok. What head gasket do you recomend ? I found a Felpro 7918PT-1 at my local checker. It lists for the 3.7 liter engine and for the w100 and w200 for 1960 L head engine.
WOW I am glad this did not happen last week as my truck was in my son's wedding hauling the wedding party from the church to my home for the reception I will post some fun pics soon.
rixm37 wrote:Thankyou Charles.
I will post what I find when the head is removed. I am relieved that some oil in the intake elbow is ok. What head gasket do you recomend ? I found a Felpro 7918PT-1 at my local checker. It lists for the 3.7 liter engine and for the w100 and w200 for 1960 L head engine.
WOW I am glad this did not happen last week as my truck was in my son's wedding hauling the wedding party from the church to my home for the reception I will post some fun pics soon.
Thanks again Charles
I'm not sure you have chosen the correct gasket, the M37 engines were spec'ed in the early 50's, even though they are in trucks that are years newer than that. We always order a head gasket for a 230 Dodge engine, 1952 year. Ours come from NAPA.
I took off the aircleaner andI saw oil in the bottom of the intake under it. [/quote wrote:
someone correct me if I am wrong, but the stock air cleaner in the M-Series is an oil bath style so there should be oil in there. There's plenty in mine! Apologies if this was NOT the oil you were referring to.
Yes the air cleaner bowl should have oil in it up to the level line. What this gentleman is speaking about is the small amount of oil that always collects in the air cleaner elbow down below the actual air cleaner. I thought this too was what you were speaking of in your original post.
Thanks again Charles. After thinking it over I called VPW and ordered one from them to take the guessing out of it.
I have started to remove the head. Those old bolts have been in there for 55 years. I got them all started and then soaked them in WD40. I am waiting for tomorrow to take them out. I hope I don't break any.
And yup I was talking about the oil that settled in the elbow. Maybe it's time for a K&N conversion and keep my oil bath for show. Maybe stick it out the fording snorkel hole.
Hey MonkeyMissle no question is a problem. These trucks are old and have lots of particlar old style parts and pieces. Everyone here is up for answering questions. I couldn't do this with out help from all the great people on this forum.
rixm37 wrote:Thanks again Charles. After thinking it over I called VPW and ordered one from them to take the guessing out of it.
I have started to remove the head. Those old bolts have been in there for 55 years. I got them all started and then soaked them in WD40. I am waiting for tomorrow to take them out. I hope I don't break any.
And yup I was talking about the oil that settled in the elbow. Maybe it's time for a K&N conversion and keep my oil bath for show. Maybe stick it out the fording snorkel hole.
Sounds like you are on the right track. I would suggest you get some GOOD penetrating oil, WD40 leaves a lot to be desired. SILI-KROIL from KANO Labs is the best we have used. Spray the bolts again, run them back down, loosen, spray again, back down, etc until they come out easily. Shouldn't have a problem since all broke loose for you.
I know some get tired of hearing me speak about compression testing. Thought I'd share this that happened here on Friday morning. A gentleman came by with a '46 Dodge 1 1/2 ton truck on his trailer. Asked me to have a look at the engine about some freeze plug & minor oil leaks. He said it cranked & ran really well. When we attempted to crank it, I saw right off his idea of good cranking & mine were far apart. Well, like I generally do I explained to him that we would first do a compression test to get an idea of the general engine condition. He asked if I could do a test, I did & found only 1 cylinder at 100 PSI, the rest were like 40 - 60 PSI. Right up front we knew that a dripping freeze plug was the least of his problems, no need in spending $$ addressing minor leaks when the engine despirately needs a rebuild job to function decent.
OK sucsess not a single broken bolt. I could not find the oil you recomended Charles, but, I got some called PB penitrating oil at the auto parts store. I did like you said, back and forth lots of oil wait in between more back and forth and they all came out . Now I am going to take a picture of the bolts location in the head before actually lifting the head off.
Well the head is off and not too good inside ! One cracked valve exhaust #6 . No real obvious sign of a gasket blow out between #5 and #6. Here's a couple of pictures. Can you replace one valve and grind the rest? I can post more pics if it will help get some ideas.
Well, you still have a problem with #5 also in some respect. You'll have to clean it up, looks extremely dirty in the photos. I would pull all the valves for a thorough clean up to include guides. You'll need to check stem to guide clearance after clean up, if it's worn out of spec, new guides & valves are the only fix. Something was causing a leak on #5 also, you need to seek out whatever that is. Be sure to number the valves so they can go back in the same guide. After a good cleaning, I'd check everything carefully including cylinder walls. If they are out of round or show much wear, I would go ahead with a full rebuild as a valve job still won't produce a good running engine. I'm a little skeptical after seeing photos, usually when the internals are so dirty, the overall outcome isn't good.
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HELP please Thanks Rick
