My 272 has been making banging sounds at first startups until warmed up and then lately barely running and really rough....acting as if timing is off. I pulled engine from car (my first thought was to replace engine /trans with something newer, but after seeing what everyone is saying here about keeping car stock thought best to fix and reinstall). Backyard mechanic but not sharp enough to know where to start to see what the problem could be. I thought once the oil pan was off I would be able to see something broken under there (banging sounded like in that area at rear bottom of engine) but now thinking maybe timing chain may have broken....not sure why? So far the only thing off engine is oil pan so asking if there is way to tell if chain is broken without taking front off or if I should be checking something else. In a perfect world I would just drop it off at machine shop and say fix-it but I don't have a thousand bucks or more to be doing that.

I do have an engine stand but so far only resting on a cart. Should I start tearing down? Car ran perfect before and even after the banging started once warmed up until lately. Pretty much at a loss here and I know this the Technical section but couldn't find the Engine Repair for Dummies section

You should be able to see the timing chain with the pan removed. If it broke, the engine would not have run at all.



The banging could be a result of the engine being plain wore out. It's probably just time for a rebuild. You can examine the main and rod bearings and crank journals without having to take it too far apart. You can use a flashlight and examine the cylinder bores. Take it apart, see what it needs, and give it what it needs.

You'll have to find out what's wrong, but I don't know if you'll really be able to fix it for under $1000. If it turns out the cost is higher than you expect, a better approach might be to find a running engine to drop in while you repair this one or just plan for it to be a long project which you work on as money allows. Whenever I try to determine if I can afford a project, I remember something I heard a long time ago. If I can't afford to do it right the 1st time, then I can't afford to do it a 2nd time.


Lawrenceville, GA

With the sump off you can check to see if it is major drama - apart from piston condition.

You should be able to see if the timing chain is still intact from the bottom, though the view is pretty limited.

It is probably a good idea to take the rocker covers off and check that the pushrods are all sitting where they should.

Just make sure that the crank is not hitting the oil pickup.

If you can turn the engine over whilst sitting on a stand, you should be able to feel any knocks whilst turning the engine over by hand.

Check the condition of the engine oil in the bottom of the sump. It should be free of filings. If there are any it is not good.

You can be lucky and it may be something simple.

Good luck.

Rick - West Australia
Do Y Blocks Downunder run upside down? Gravity Sucks!!

I just wanted to highly recommend that you use an engine stand that has FOUR wheels on it and NOT THREE. These Yblocks are very heavy and unstable. Pete

Before you take the bottom apart, have you had the rocker covers off? It could be something simple like a bent or broken push rod or a valve hanging open.

Kenneth

Fredricksburg, Texas

Ken, they are my thoughts exactly, so simple to do and common problem. interesting to see result. regards bill.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Automatic transmission?  If so, then for the banging noise take a look at the flexplate that hooks to the converter and check for cracked or broken ears.

Lorena, Texas (South of Waco)

Thanks to all for the help, yesterday spent day at a Birthday Party at local airport viewing antique airplanes and eating pizza and cake, and today raining here in sunny California so tomorrow for sure I'll be checking engine now that I know where to start. Car does have auto trans so the flex plate is good place to start. Thanks again!

Not sure which is flexplate and what is the converter. In the following pictures is the converter still in the car and is the flexplate fastened to flywheel? Man, I feel stupid.

 Is this converter?

 Is this the flexplate...and are these fins broken off (didn't find any pieces also no sign of metal shavings in oil pan) or is the thing made this way? To remove do I only need to remove the bolts shown?

This picture is of the converter. The converter is fastened to the flex plate, which is in turn fastened to the crankshaft. The flex plate is the piece with the gear teeth on it. I think you will find the nuts (or is it bolts) for removing the converter on the engine side of the flex plate.



You found metal shavings in the engine's oil pan? Oh, never mind. You said no sign.


Lawrenceville, GA