Pontiac 400 engine

Can anyone tell me what torque is necessary to turn the engine over with the spark plugs out, please.

Reply to
David Toft
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With the plugs out it shouldn't take hardly any effort to turn the engine over. I'm assuming you're using a large ratchet and socket on the balancer bolt. If this is an older engine or one that's been setting for a while load the cylinders up with WD40, let it sit overnight, then try it. That will hopefully break the rings free of the cylinder walls and prevent any scoring when you first move the pistons.

Reply to
FBR

This is an engine which runs. It starts OK cold but the starter will not crank it when it has been warmed up, the current it is pulling makes smoke come out of the starter motor. I took the plugs out and put a socket and torque wrench on the balancer bolt, it took 50 lb-ft which I thought was excessive.

Reply to
David Toft

I had the same problem on my 455 and found out I had not spaced the starter correctly. There are shims available to space the starter from the block otherwise the gears will bind into themselves and cause the over current situation. Good luck.

Reply to
starhop1

With the pugs out and the trans in nutural, you can spin it by hand by pulling the belts, depending on how may pullies area attached. Had a

79 with the 301 and just the power steering pump and alt. No trouble turinging it.
Reply to
brxsep

Sorry for the late response but this sounds more like a timing issue. Advanced timing causes hard starting when warm. This might solve your problem.

Thanks

Collector Car Central LLC

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From Project to Perfect, Classic Cars for everyone.

Reply to
<cccentral

I have been investigating a "death rattle" and found a very bent push rod. It wasn't bent when I put it in about 200 miles ago, Has anyone any suggestions as to why it bent please.

Reply to
David Toft

Hi David,

Tuesday June 07 2005, David Toft writes to All:

Maybe the valve seized up for some reason, then the rod bent? Just a guess.

Kevin

Reply to
Kevin Klement

What year model is the engine? Isn't this the engine you said was hard to turn over with the plugs out? You said the pushrod wasn't bent 200 miles ago; why did you have it out? I'm beginning to see something that makes sense here. Let me know. AW.

Reply to
Andy Warren

In article , Andy Warren writes

The full story is that I bought it as a non runner with a "reconditioned" engine already fitted. The car is 1978, the block 1974 and the heads something else. I couldn't turn the engine over at all, so I took the heads off thinking it might be because a piston had rusted in its cylinder. I found that 7 of the pistons were in the wrong way round, so I took the sump off to fix that. I then found that ALL the big end caps were on the wrong rods. The crank looked as if it had just been reground and all the bearing shells looked new. I put all this right and the engine turned over OK. It has been fitted with an oil cooler and remote oil filter. The oil filter is about twice the size of a standard one and is fitted high on the R/H inner wing, what didn't strike me as significant was that it was fitted upside down. I had many, many attempts at getting it running properly, the timing was way out, the leads were on the wrong plugs, the electronics in the distributor were open circuit, the carburettor was flooding, the starter motor wasn't shimmed correctly, etc, etc. Every time I tried to start it the oil filter had drained (because it had been fitted upside down), so that had to be filled before anything got to the bearings. I think the very tight engine is caused by the fact that it is partially seized. I have just taken the crank for regrinding again as the journals are in a terrible state. I also noticed that there were several (relatively) large pieces of black plastic in the oil ways of the crankshaft, some of which had parts of a fine internal thread on them. Any idea what this could have been?

Thanks for any advice,

Reply to
David Toft

Now that is one heck of a "rest of the story". It seems like the person you bought the car from shouldn't be building engines! It also sounds like you know more about engines than they did, being able to spot reversed pistons etc. I hope they haven't "fixed it to death" when it comes to the engine. That

400 is an awesome engine. Bigger than most but not too big. I would like to see a picture of the mystery black parts in the oil gallery of the crank. If you can photo it on something of scale that would be great. It sounds like some type of shipping plugs that are fitted into parts to keep out debris until it is to be used. Like they were not removed and the part installed anyway. I do have some suggestions:
  1. If feasible, put the stock oil filter arrangement back on.
  2. Do you know what "plastigage" is and how to use it? Since the engine was run misassembled, the plastigage will show you if a connecting rod is bent. If a rod is bent, it is not usually visible.
  3. Remove the oil gallery plugs in the block and blow out every oil passage.
  4. If you have the crank out of the block then you have the pistons out as well. Check the piston ring end gap in the bore of the block. If the guy that built the engine first couldn't put pistons in frontward, he didn't check this.
Reply to
Andy Warren

These are the bits in the crankshaft, not a very good picture I'm afraid.

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scale is in millimetres This bit was under the bypass valve in the oil filter mounting casting.
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the scale is millimetres Apart from the remote filter the car has been fitted with an oil cooler and a thermostatic bypass valve. I am beginning to suspect that the bits came from this setup as they are too large to go through the tea strainer on the oil pump pick-up let alone the oil filter.

Already doing this, just got to sort out a suitable filter

I don't think they are as there are no unusual wear marks on the pistons or the bores

This is Monday's entertainment.

I intend to do this.

Reply to
David Toft

I think you are right on the money. I don't know how the cooler is plumbed in relation to the filter, but the debris came from one of the two. It's amazing how someone can add an oil cooler and a remote filter to make the engine last longer and wind up causing it certain death. Keep us posted....

Reply to
Andy Warren

Im not a Pontiac engine man (I like them but I don't know them as well as some here). If I found crap like that in a engine I bought, well put it like this, shallow grave for the idiot.

First thing you need is a Pontiac specfic engine manuial. You need to identify every part, know what you have, and make sure it's all compadible.

Next you need to remove the remote filter stuff, and the oil cooler stuff. Here in America in the summers 100 to 105 degree air temps (37C to 41C roughly)are commen. Pontiac engine survive that here with out added oil coolers.

Finding Pontiac engine parts over there is like me trying to get Sterling or Morgan engine parts here. Not very easy. Your best bet it to deal with companies like Northern Automotive, Jegs, Summit & Egge Engine Company. They will all ship to you.

You should probably also email snipped-for-privacy@aol.com He hasn't been on the group lately, but he is a pontiac restoration expert.

Charles

Reply to
Charles Bendig

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