engine turning over and stalling while driving

[tygman]

1991 350sdl.

Ok first off, it only starts in neutral - i am assuming the neutral-safety switch.

The other problem, which I cant associate with any factor, seems to be completely random, is that the engine will turn over when starting. It will sound like its starting normally, and then "die" and shut off. After a few tries, usually a few minutes it will start. Very annoying.

The other thing is that while driving, always when under 10mph or so, the same noise / engine turnover will occur sometimes. Completely random. It sounds like the engine is trying to stay alive but cant, and just dies.


I recently noticed my oil engine levle light go on. Checked the dipstick and it is on absolute minimum. I got an oil change a few months ago, don't see how I could lose 8 quarts of oil in a few months without see 1 leak under the car. You can see some oil marks on the engine block/cylinders, but I was told this was normal. Not something that would cause 8 quarts to go.

The engine shutoff problem has been occuring more often recently, wondering if it had to do with the low oil. But it has happened before wheny my oil levle was fine.

[TMAllison]

1) Sounds like a bad NSS.

2) Sounds like you have a fuel/air leak creating a hard start condition.

3) Not sure I understand. Is the starter coming on? Dieing at 10mph suggests fuel delivery problem or massive intrusion of air.

4) Min-Max marks usually represents 2 qts. Not 8. Put one in and check it.

[tygman]

Thanks your post helped me a lot with the oil issue. Will check it after putting in a quart.

Ok I'll try to explain the starter situation. The car does turn on, makes the normal turning on noise, and then a second later dies, sort of like a knocking noise and dies.

The air issue sounds plausible. I changed both my fuel filters a few months ago. The fuel prefilter has 3 air bubbles in it, I was told small air bubbles are normal. Two of the three air bubbles are tiny - maybe 1/8" diameter, but one is large, about 1.25" long.

Could this cause the engine shut off problem? I am thinking the reason it doesnt happen at high speeds because there is more pressure then and more fuel rushing through the system, but at lower speeds less fuel and more change that the air bubble could be affecting it?

Ive also heard water in the fuel (which is essentialy air in the fuel) could bea culprit, and I think I've had problems with that in the past when I got diesel from a cheap gas station, but that shouldn't be the case here, seeing this problem exists regardless of the gas station I use. Only other thing to note is that I put a can of diesel hi-test in my last fill up.

[TMAllison]

I cant find an exact picture of your pump but should look approx like this one http://www.detali.ru/cat/oem_mb2.asp?TP=1&F=123132&M=617%2E912&GA=722%2E118405&GM=716%2E005++++++++++++++717%2E400&CT=M&cat=143&SID=07&SGR=045&SGN=01 See #11 in the first photo. It is your manual primer pump and if has a white cap is the old style and is oftentimes the cause of air leaks on older IP's. Check to see if there is any leaking/wetness there.

The new style is black, much smaller and does not have to be unscrewed to use. Is fairly cheap and failrly easy to isntall.

[P.E.Haiges]

tygman.

WHat do U mean by "turns over" ? This is a confusing and poorly used term. Pancakes turn over but engines?

[rrgrassi]

I do not think the SDL has a manual primer pump.

TYGMAN,

Water in the fuel is not the same a air. Air can cause missing, poor running, of even stalling. Water is nastier in it's tricks and can cause IP problems due to the expansion rate of water that is turned to steam.

You do have the '91 SDL. How many miles are on it? Also do you know if your engine has the updated connecting rods?