More trouble in M38A1 land

Deadguy · Post by **Deadguy** » Wed Feb 20, 2013 10:52 pm

So, last I posted, I had slammed into a median, up onto it, and back down. I checked for damage, didn't see any, and continued on my journey. Ten minutes later, the engine dies, and I can't restart it, because the starter foot switch is jammed.
I finally got it apart today, and and it turns out the foot pedal for the starter in now hitting the engine block a little on the left side, that's why it's jammed. So, we figured maybe that hard hit made the engine block shift on it's mounts ever so slightly (like I said, I looked underneath and see no other visible damage.) So I get it started up, head down the road, and it's fine for a little bit. The the engine is hesitating, and won't do over 30. Then It dies. I restart it, and am driving slowly back, and it hesitates and dies two more times. I'm going even slower now (like 12 miles an hour) and it starts making a clattering noise. I rev the engine a little more, and it increases. I keep going, and it dies again. I get it restarted, sitting on the side of the road, and the clattering noise is pretty loud. I pop the hood, and it appears to be coming from the engine block, high up like near the valve cover. I shut it down, had my buddy tow it all of 1/2 mile, and will look more closely tomorrow. If anyone can give me any heads up an what to look for, I'd be much obliged.

Post by **wesk** » Wed Feb 20, 2013 11:02 pm

1-Pull valve covers and check valve train for excessive clearance or broken or loose parts.

2-Do a compression check.

What was the oil pressure during these events?

Deadguy · Post by **Deadguy** » Wed Feb 20, 2013 11:51 pm

I have the third oil pressure sender in there, and a newer (like M151) gauge. It varies alot, so I use my manual gauge at home just to double check. So, reading on the road, it was like 30PSI (which seemed a little high for idle) but like I said, it's unreliable. The clattering noise only started tonight, but it died in a similar fashion a week ago when I was talking about all my jumping up a curb troubles. I restarts even now, but it's at my buddies shop ( I had it towed there, he has a lift).

Post by **wesk** » Thu Feb 21, 2013 12:10 am

Since you are using the jeep as a driver you should install a mechanical oil pressure gauge in place of the unreliable electric unit.

Check your body tub mountings. The accident last week may have moved the tub a bit causing the misalignment with the starter kick pedal. Don't just eyeball them. Get a pry bar and check them for movement. Have a couple of guys grab the side and rear of the tub and try moving it side to side and forward aft. It should flex more than 1/2".

Deadguy · Post by **Deadguy** » Thu Feb 21, 2013 12:25 am

I'll check. What could it have done to the engine? I hit the tires and rims hard, not the frame.

Post by **wesk** » Thu Feb 21, 2013 12:46 am

The current engine issue is probably unrelated to your accident.

Your jeep was a recent resto. That means the opportunity for loose bolts and shrinking rubber pads is high. Throw in a rapid deceleration and heavy jarring when you jumped the curb the tub could easily have shifted. This is obvious since you said you found the starter kick lever misaligned with the starter kick pedal.

Deadguy · Post by **Deadguy** » Thu Feb 21, 2013 1:03 am

Cool, thanks Wes. The engine is a recent rebuild, and as I've posted, I've already had problems with the first rebuild. It started knocking, the same guys, under "warranty" , took six months to pull it apart and put it back together, and announced nothing was wrong with it, so I owed them $500. Plus I spent another in shipping.

Deadguy · Post by **Deadguy** » Thu Feb 28, 2013 12:05 am

Took the valve cover off and went over the engine with a mechanic's stethoscope. It's definitely coming from the lower block of the engine. Which means the engine needs to get pulled. Again. Does anyone know a rebuilder, preferably one in Pennsylvania? Does Army Jeep Parts do rebuilds?

Post by **wesk** » Thu Feb 28, 2013 12:35 am

Make sure it's not the fuel pump or the crank front slinger first.

Deadguy · Post by **Deadguy** » Thu Feb 28, 2013 12:41 am

What would I check on the fuel pump, and what is the crank front slinger? The oil slinger inside the timing cover?

Deadguy · Post by **Deadguy** » Thu Feb 28, 2013 12:55 am

The knock is louder the higher I rev the engine. I put a little straight 90 weight in there and it quieted down a little, then I reved it and it kicked right back up.

Post by **wesk** » Thu Feb 28, 2013 2:25 am

If you are experienced enough to discern a rod knock from a crank knock from a front thrust washer knock from a fuel pump arm knock, from a piston pin knock then by all means have at pulling the engine out again. If you are not that sure about what kind of knock you have then get a trained ear in there before you do all that work.

Deadguy · Post by **Deadguy** » Thu Feb 28, 2013 11:42 am

I can't. My friend, who is a mechanic at an auto repair shop, wasn't sure what it was either, just that it was louder lower down on the engine, and noiseir the higher I revved. We went over the whole thing last night. Can you tell me what to check for, I'll look again tonight.

Post by **wesk** » Thu Feb 28, 2013 10:19 pm

Just remove the pump and run the engine. No knock fix the pump. You only need a little cover over the opening and you only need to run it for a few seconds.

Pull the side valve cover and check for loose cam/valve train parts.

If the knock is still there pull the front timing cover and check for loose parts on the crank. Check crank end play.

Pull the oil pan and check each rod for looseness. Check to make sure the correct rods are in the correct cylinders and the rod itself is facing the correct side of the block. Some blocks the rod can strike the skirt or webbing causing a knocking sound. Check that the crack and rods are not hitting a loose or wrong type oil gallery plug. There are three of them inside the engine. Sometimes these issues don't arise until the engine is run in awhile and there is some wear to the new bearings.

The low end of the block includes all those moving parts shown which are below the #2 piston skirt.

If "A, B, E. or F" are missing a knock can develop. If "L or N" get loose a knock can develop.

Any damaged hardware in the satck of parts above the cam can cause a knock. Excessive camshaft end play can result in a knock.

Everything I have pointed out above can be checked with the engine in the jeep. Any experienced mechanic worth a salt would have suggested these items get inspected.

Deadguy · Post by **Deadguy** » Mon Mar 18, 2013 12:26 pm

Definitely not the fuel pump. I'm towing it over to L&M engines (the guys recommended to me by Army Jeep Parts) today. They are like 20 minutes away. We had an old mechanic who's worked on alot of these types of engines over and he said it's probably a wrist pin.