My overhauld engine.

1959 - 1978, M151, M151A1, M151A2, Technical questions and discussions, regarding anything related to the M151.
Post Reply
Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

My overhauld engine.

Post by Swem151 » Fri Aug 03, 2018 11:37 pm

Have some questions about my overhauld engine.

The springs looks a little slack to me or should they be like this?
Image

Sparkplugs at cylinder 1 and 2 gets sooty.
Replaced the intake gaskets wich was leaking but still they get sooty.
And the engine hesitate when revving it up.

Image


I know im still breaking in the engine but still after the first oilchange the oil looks shimmery and this grey stuff was stuck at the oilplug magnet.

Image

Engine lash normar?
https://youtu.be/kYX5MSRAsp0

And the engine running with some sort of nocking?
https://youtu.be/AWO5cf2rTJE

Rickf
G-Lieutenant General
G-Lieutenant General
Posts: 4647
Joined: Sun Mar 19, 2006 12:04 pm
Location: Pemberton, New Jersey

Re: My overhauld engine.

Post by Rickf » Sat Aug 04, 2018 5:58 am

The distributor springs look normal, they are in the relaxed position and will tighten as the centrifugal weights move out. The engine is new so the plugs will not be perfectly clean until it breaks in some. The backlash, I can't really say since I have not checked mine out but it is gear drive and there is no way to adjust it. When running the is the timing mark bouncing around? The engine sounds just fine, the noise you hear is most likely the vacuum pump. Put a long screwdriver against the pump and hold the handle against your ear and see if that is the sound. If not you can move the screwdriver around until you find the sound. The oil would bother me, after doing any machine work did you thoroughly clean the block with hot soapy water? Run it for a little bit and see if you get more and if you do them pull the oil pan and check the bearings. Also run a magnet through the oil and see if it is magnetic or if it is not, if not it is bearing material. Your oil pressure is good so I don't see any immediate alarms. Did you check the ring end gap before installing the rings?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Sat Aug 04, 2018 9:19 am

When running the timing mark does not move around.
Yes i cleaned the block a couple of time to be sure it was clean from debries.
The grey stuff was magnetic but the shimmery cupperpast looking thing in the oil is not magnetic.
When installing the piston and rings i checked the gap wich was just at the edge to be to big.

When runing in a engine the oil should look like this i have heard because everything is new and must wear in?

Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Sat Aug 04, 2018 10:07 am

Hard to see the shimmer but this is the oil.

Image

Rickf
G-Lieutenant General
G-Lieutenant General
Posts: 4647
Joined: Sun Mar 19, 2006 12:04 pm
Location: Pemberton, New Jersey

Re: My overhauld engine.

Post by Rickf » Sat Aug 04, 2018 11:07 am

If you change the oil a second time and you are still getting that then you need to investigate. It is normal to get some debris but that looks like a bit more than I would normally see. The oil appears darker than I would normally see after a short run also.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone


Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Sun Aug 05, 2018 2:19 pm

So this is conecting rod no1.
Image
Image

No4
Image

Crankshaft bearing no1 from radiator.
Image

Thats all i have checked tonight.

Rickf
G-Lieutenant General
G-Lieutenant General
Posts: 4647
Joined: Sun Mar 19, 2006 12:04 pm
Location: Pemberton, New Jersey

Re: My overhauld engine.

Post by Rickf » Sun Aug 05, 2018 5:56 pm

#1 connecting rod top half looks like the bearing was too tight. Did you plasigauge the bearings when you put them in? Was the crankshaft machined? what size were the bearings? The other rod bearing looks ok but not real good for a motor with no time on it. I could not enlarge the main bearing picture so I could not really see any detail. But too me it kind of looks like maybe the wrong size bearings were used. Here is the problem, that bearing metal is not magnetic and you said the metal in the oil was magnetic. The only places you will get fine metallic powder is rings against cylinder walls, distributor gear against cam gear or timing gears hitting something.
This is really hard for me to diagnose from afar since I cannot physically see or feel the engine.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Sun Aug 05, 2018 11:18 pm

The crank is indeed machined to .010 and the correct bearings is used.
Yesterday i used a caliper gauge , the rod on the crank says roughly 50.5 mm and original should be 50.75 minimum.
50.75 - 0.254 (0.010 inch) = 50.496 mm so im using the correct bearings.
Yes i know i should use plastigage but back then when i put it all together i only used micrometer.

But when you feel and see a lash as i did it is usualy to much i have learn.
Could this be a result of a oilpressure problem?

Rickf
G-Lieutenant General
G-Lieutenant General
Posts: 4647
Joined: Sun Mar 19, 2006 12:04 pm
Location: Pemberton, New Jersey

Re: My overhauld engine.

Post by Rickf » Mon Aug 06, 2018 5:21 am

It could have been from a lack of oil in the beginning, did you coat the bearings with oil or assembly lube when you put it together? You have good oil pressure now so that tells me the problem is not a bad oil pump or a bad cam bearing. You were revving it up pretty good in the video and the bearing are not wiped out so they are getting oil. Granted it is under no load but they do not look oil starved. But I go back to what you said in the beginning and that was that the shimmer was magnetic. That is steel and the bearings are not steel nor are they magnetic. Here is what I would suggest you do. Those bearings are not bad from the look of them. Get some plastigauge and following the directions check all the bearings and if they are good then put it back together and run it and see how the oil looks at the next oil change. Use a quality oil filter, I use only Wix filters. Any debris that was going to come loose from the initial break in has already done so, you may get a little but of dirt as the rings continue to wear in but you should not be getting any more metallic shimmer in the oil. When using the Plastigauge be sure to wipe off the bearing and crankshaft with brake cleaner so it is dry, do not rotate the crank. Do your check on all of the bearings and then remember to oil the bearings before bolting them back up. All will be fine after that.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Mon Aug 06, 2018 11:02 pm

Yes i coated with assembly lube and engine oil.
What if the crank was poorly polished, might that causing scratches on the bearings?
I can see with my eyes the surface have some spots on it.
The shimmer in oil looks like cupper is not magnetig.
The darker on the paper was.
And the darker material is also camshaftlube.
I also found a small shiny magnetic piece in the oilsump.
So you believe i can still reuse this bearings?
Last edited by Swem151 on Mon Aug 06, 2018 11:14 pm, edited 1 time in total.

Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Mon Aug 06, 2018 11:07 pm

Image

Rod from left 1-4.
Image

Image

Image

Image

Rickf
G-Lieutenant General
G-Lieutenant General
Posts: 4647
Joined: Sun Mar 19, 2006 12:04 pm
Location: Pemberton, New Jersey

Re: My overhauld engine.

Post by Rickf » Tue Aug 07, 2018 5:32 am

Those bearings do not look bad. They look like they may have had some residue run through them that possibly was left behind in the oil galleys. They are far from bad and your good oil pressure supports that. Like I said, since you have it all apart. Check it with palstigauge just for piece of mind and then put it together and run it. I was not thinking about the cam lube making the oil dark. I did not realize you put in a new cam and lifters. I think the engine is fine from what I see. The finish on the crank looks perfect and that little piece you found looks like a drill chip and could have come from anywhere. If that were from an engine problem there would be a lot more of it and other debris. Run a good (Wix) oil filter and do an oil change after a few hours on the engine and after that you should have no worries.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Swem151
G-Corporal
G-Corporal
Posts: 28
Joined: Fri Jan 10, 2014 1:29 pm

Re: My overhauld engine.

Post by Swem151 » Wed Aug 08, 2018 4:31 am

Plastigage is now orderd.
The engine is not apart only oilpan and the bearings.
Posted the images on facebook and they also believe there is some residue gone thrugh them.
Never heard of wix filter so i use Mann w940/1 or Bosch filter wich is quality filter in sweden.

Rickf
G-Lieutenant General
G-Lieutenant General
Posts: 4647
Joined: Sun Mar 19, 2006 12:04 pm
Location: Pemberton, New Jersey

Re: My overhauld engine.

Post by Rickf » Wed Aug 08, 2018 7:34 am

I am familiar with the Mann line of trucks and heavy engines but have never worked on them. I am very familiar with Bosch products, I would think either are good choices.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Post Reply

Return to “M151's Technical Knowledge Base”

Who is online

Users browsing this forum: No registered users and 1 guest