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jonny2shoes

Newbie with 302 question

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Hello All,

 

I'm new to the forum and recently just purchased a '75 280Z with a built 302 V8. I apologize in advance, this post may be long.

 

After about a month of ownership I noticed a ticking coming from the engine that was pretty pronounced. I suspected a lifter or that a general tune up was needed. The car runs very strong, and has not had any performance issues that I can detect, but I also don't have anything to compare it to. 

 

Fast forward to this week. I dropped the car off with a local hot rod shop to go through the heads and adjust the valves, etc. Once the valve covers were off, the guy noticed there was a small metal ring down in the head just laying between the valve springs. It was determined it dropped out of the valve cover gasket, as the gasket had 6 small ringed shims where the bolts go through to attach to the head. His theory is someone removed the valve covers and then tried to re-use the gaskets and while pushing the bolt back through the hole it dislodged the ring into the head.

 

He says he also found one that was cut in half upon further inspection; as well as metal on the underside of the valve cover.  He also noticed there were more shims missing from the valve cover gasket and he suspects they went through the oil drain back holes in the head and dropped down into the engine. He sent me a picture of the ring he found, but by the time I got to the shop, he had thrown all the rings away from both gaskets.

 

He is telling me now that I should pull the engine and have it rebuilt because he suspects this material floated through the engine to the crank and bearings and will cause me issues in the future. He said I could pull the engine myself and bring it to him and it would probably cost around $700-800 to rebuild. If he pulls the engine it will cost anywhere from $1,700 to $2,500.

 

My question is, should I be worried if these rings went down the oil drain holes? Don't those holes go straight back to the oil pan, where they wouldn't be able to be sucked back into the engine? I plan to drain the oil through a filter and see if I catch any shavings. I want to be catious, but I also don't want to needlessly rebuild the engine. I haven't had valve covers off since I owned it until now, and the previous owner owned it for 2 years with no issue, so if someone pushed these rings into the engine accidentally, they would have been there for a while.

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Those rings, if they are there at all, are at the bottom of the oil pan and will most likely stay there. Even if they did get stirred up they wouldn't get past the screen on the oil pick up or the oil filter, sounds like the guy is trying to whip up a job for himself. No reputable mechanic rebuilds and engine because there 'might be' something wrong with it. Have the valves adjusted if that doesn't clear up the ticking then have a wet/dry compression test done, if the numbers are good then button it back up and enjoy it. If the numbers are inconsistent then have a leak down test performed to find out where the problem lies.

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Well I drained the oil. No shavings found, even running a magnet through it. Had it compression tested a few weeks ago before the ticking started and compression was around 125lbs across the cylinders. I have had some oil consumption and blue smoke when warm. Previous owner had deleted the PCV and was running just a valve cover breather, so I reinstalled the PCV and the smoking had gotten much better, but not completely gone. Seemed to be down almost 2 quarts of oil though, which was concerning.

 

I did happen to find one of the rings in the valley of the head on the driver's side that he hadn't thrown away. The material was pretty hard and small enough to have gone down the oil drain back, but again I wouldn't be worried about that, if I knew those holes went straight to the pan and nowhere else to go in the engine.( which it sounds like they do go straight to the pan.)

 

The shop's concern was with the one ring they found that had been cut in half (I'm assuming it got caught in a valve spring) and that potentially it could have sent metal through the engine specifically to the crank and bearings.

 

I'm a novice when it comes to engines, so I don't really have enough knowledge to tell if I'm being sold a load of crap. The engine is easy enough to pull as I don't have power steering, A/C, emissions besides O2 sensors, etc. so I was thinking of pulling it and just taking it to an engine builder to have it rebuilt anyway for piece of mind.

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I like to run a magnet on my oil pan (stuck on the backside or somewhere it won't get knocked off) just for those little filings that make it through.  Granny's right though, There's a good screen on the oil pan pickup that will clog up before it sends pieces of engine back through your pump.  I had a 300 I6 with the later model phenolic timing gears; the gears got chewed up and clogged the pickup entirely. (No oil pressure over 1600rpm!) Cleaned it all out, changed the gears and I was all set.  

 

I PERSONALLY wouldn't rebuild it, but if you won't be able to enjoy the car or will always have a fear of it blowing up on you far from home, then knock yourself out, get it rebuilt.  Then you get an excuse for performance parts too!  (at least a new bumpstick, valve springs etc) 

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I wouldn't rebuild unless it really started acting up. Is it a stock 302? They're basically a dime/dozen, even if it blows up just get another short block or build a fresh motor. Did you check your oil level and pressure when it started making noise? Roller or flat tappet? The latter tend to be noisy, especially if oil level starts to dip. 

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Thanks for the responses. I ended up just pulling the engine myself and taking it to a local machine shop to have it rebuilt. After draining the oil, I was a little concerned as the car was down nearly 2 quarts, and I just changed the oil less than 300 miles ago. I was also having some blue smoking issues as well. The original owner had blocked the PCV system and was just running breathers, so I reconnected it all, and it helped, but did not fully resolve the smoking issue.

 

For the peace of mind I just decided it was best to have it rebuilt, so I would at least know what has been done to the engine.  

 

It has some decent performance upgrades such as upgraded valve springs, comp cam, aluminum heads, Edelbrock intake, Tremec 5 speed with Hurst short throw, etc. I feel like the rebuild will be worth the money to protect these parts and reduce my anxiety...haha!

 

See pic below!

 

IMG_2373.jpg

Edited by jonny2shoes

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