I'm pulling a 350 tpi out of my 87 gta. this is my first time pulling a motor... luckily with the help of a friend who is more experienced. the motor has a loud knock and we are just trying to find out whats wrong and get my baby running good again! does anyone have any suggestions on what to upgrade while the motor is out? I was thinking about putting in a bigger cam... but other than that im not sure ( as you can probably tell im pretty new with all this stuff). I was also wondering if it is neccessary to take off the water pump, alternator, and power steering pump? i appriciate any other suggestions yall have for me!

 

I wouldn't worry about the camshaft; it's a roller cam and it's re-useable. You need to tear your engine down to parade rest and measure EVERYTHING. You only need to replace what's bad when you're on a budget, but you have to know what is bad first.

Get a good manual and measure everything. Then get back to us.

 

I usually leave the power steering pump in the car. The water pump can stay on the engine and so can the alternator, just disconnect the wires. Also, if you have A/C and it still works I'd leave the compressor in the car. I mean you can remove whatever you'd like but it seems easier to pull the motor as whole as possible and just use an impact gun to remove everything.

 

When i pulled my motor i left everything on the motor.... just disconnected the wiring harness and misc lines and it was set to come out.

 

thanks for the tips... i started disconnecting everything today and it looks to me that i wont have to take the water pump, alternator, or power steering pump off. we got everything disconnected and are planning on disconnecting the tranny tomorrow. because of limited time, hopefully i'll have the motor out on monday. thanks again for the help and ill let you know what i find inside ol beastie... hopefully nothing too screwed up!

 

take the wiper motor off before pulling the motor or most likely you will hit it and crack or brake it

 

just pulled the motor tonight... good advice about taking off the wiper motor! i found a few chunks of metal in the oil pan and found out they were off three pistons. im not sure what its called, but the pieces were from the "lips" of the piston at the bottom. There are two "lips" and three of them were broke on the inside. does anyone know how these pieces broke? would that be the cause of the motor knock? im guessing it is something else that is causing the knocking. tomorrow i am going to check the bearings and see if everything is good there. what would be the next step?

 

Those are called the piston "skirts".

Has this engine ever been apart before?

 

yea the guy who sold it to me rebuilt the engine about 10,000 miles ago.

 

so how would the piston skirts break? does it have to do with the timing? does anyone know what the connecting rod deviances are for a small block 350? im looking up torque specs for my gta and I was wondering if it is a pontiac or chevy motor? i thought it was a chevy but i found specs for pontiac motors also. thanks for the help.

 

Either put together incorrectly, or wrong parts used.

 

just check the casting number and as far as the skirts breaking it could have just been crappy work or like five7kid said...wrong parts

 

ok, wow, first off, change the crank bearings, meaning take off all the crank mains, pull the crank up, do not remove, slip in the new ones, PROPERLY LUBED!!! they are like 35 bucks from advance auto, check it out, partsamerica.com will show you them. new double roller timing chain is very inexpensive and will do you wonders, if you want some looks, chrome timing chain cover form autozone, 20 bucks, fuel pump blockoff plate, chrome 8 bucks, headers from advance auto, 98 bucks, try a new distributor while your at it, yea, its expensive, but wow, they do you wonders, and are better than stockers, and make sure you take a magnet to those metal shavings before you put on that pan

 

thanks for the comments.

when you say wrong parts, do you mean wrong pistons?

 

what is the difference between a double roller timing chain and a regular timing chain? does getting a new one have to do with the broken piston skirts or just for performance?

i already have edlebrock shorties- ive heard those arent the best for my car though. same question for the distributor as the timing chain... is it to add performnance or to fix the problem?

 

An absolute waste of 98 performance dollars.

Could be, or some other stupid thing like wrong rods. Pistons would be the most likely for wrong parts, but improper assembly is the most likely reason for the damage.

I would say go completely through that engine. If you don't know what to look for, take it to a competent machine shop and have them look it over for you. I would say it needs to be completely disassembled and cleaned up at a minimum - just trying to replace what appears to be broken is a recipe for needing to do it over again later.

I'll never forget the "rebuilt" engine I bought for the '57 in 1991. Great deal, it appeared. Then I discovered I couldn't adjust one rocker because the nut was metric on an SAE stud - he took care of that. A little while later, water came gushing out of the side of one head - cracked. Went to get that taken care of, he couldn't be found. A note taped on the door said, "You have my money. I don't have my engine. See you in court." A business next door said the guy hadn't been around for two weeks. Took both heads to another shop, they fixed one and replaced the other. A little while later, I noticed the oil was getting milky - chasing that down found out the block was cracked on both sides of the lifter valley. Found a rebuild shop that would sell me a standard bore block to bore out and fit my pistons to. In taking the engine apart, I discovered the rear main bearing was smeared and the groove completely closed off - apparently he put a .020"-under rear main bearing on a .010"-under crank, so I had to get the crank turned and new bearings. I had now spent more on this engine than I would have getting one from a reliable shop, so I just put the same rings back in to try to save a little money. Out of this complete "rebuilt" engine, I had used the crank, rods, pistons, rings, and one head, and had to rework the crank and head. The engine always used oil, even when things finally stayed together. I finally tore it down again in 1997 and discovered he had used .020"-over oil control rings in .030"-over bores - the top rings were fine - how he mixed rings and bearings sizes in this "rebuild", I'll never know.

The moral of that long story - you really need to go through this engine thoroughly now so you can avoid having to do it again in the future.

 

Take your block to the machine shop and have them check the cylinders for taper and have the main bore checked as well. Broken piston skirts could be caused by a few things.
1.piston installed on coonecting rod backwards.
2.connecting rod installed backwards
3.taper in cylinder walls.
I would take everything you have to the machine shop have them check everything. have them mic everything too.I have a feeling this rebuilt engine was just that.... taken apart cleaned and put back together...not reconditioned.
On your timing chain question a double roller looks like two chains side by side. looks like two chains stacked on each other and a single roller is just a single strand of chain. The chain has nothing to do with the pistons breaking.
As far as headers go I have the edelbrock shorty T.E.S. headers chrome coated, and are the nicest set of headers I have ever owned. I recomend going to NAPA and buy there nitro seal steel insert header gaskets, they are the only ones that will last for years. just did mine last year and didn't use the nitro seal and I blew them out already.