Plastic Pieces in My Engine??

[leadrsa729]

Hello -

Had a guy do a rebuild for me. Long story short I had to pick it up finally after two years on a trailer.

He was almost done, but left a list of things that still needed to be done. He told me that he had done the initial start up and had even driven the car.

I got it running, but did so from the standpoint that it had never been run before. I cranked the engine 3 times at 30 seconds a piece with the starter solenoid disconnected to build pressure. Then started it and let it run at 1,800 to 2,000 RPMs for 20 minutes. I shut it down, changed the oil, and restarted it. Set the timing and adjusted the idle. Then I drove it for 5 miles around my neighborhood until an awful sound started coming from the exhaust valve cover on the driver's side.

As a result I went in to pull the covers off. I can't for the life of me get the lower covers off. I would swear they are part of the block. They don't budge at all. Anyone have any tricks on getting these off?

Anyway, before I tried pulling the valve covers to get a good look I drained the oil. This is what I found on the sump cover screen after I drained the oil:



Does anyone know what these black and red pieces are? They are very brittle, and seem like plastic to me. Thanks in advance for your help.

[80-911SC]

i found black pieces similar to yours and after hours of figuring found them to be the cam chain ramps there are black ones and brown i think there is one brown per motor on the right side.

my valve covers some PO had put sealant on the and the upper and lower felt permanent, one swift pop with the dead blow hammer ( make sure all the nuts are off) and they dam near fell off

Hope this helps

Steve... .

[leadrsa729]

If these peices are from my chain ramps, are they deteriorating? This should be a brand new engine. Thanks for the reply.

[E Sully]

Definitely sounds like the chain ramps. Hopefully no bent valves if the timing went out.

[Aurel]

Are those pieces hard or soft? If they are soft, they could be excess sealant from the case. The bad news is that all theses little pieces could clog oil passages inside the engine. Looks like the black is the same sealant that you can see around the sump screen. My bet is that your mechanic knew nothing about Porsche engines and put way too much sealant everywhere.

[E Sully]

I would recommend pulling the chain cover and checking it out. If the tensioner failed it could lead to damaged chain ramps, as well as the valves hitting the pistons. Could have been that loud noise you heard.

[mca]

It is Loctite 574.

I found a couple little pieces on my sump screen too. My guess is that the excess sealant squeezes inside of the case - then breaks off. I always assumed that the 574 would remain soft. Guess not.

[leadrsa729]

I guess my first order of business is the get a piece of wood and see if I can't knock off those lower valve covers with a rubber mallet.

Then I go to the timing chain covers to see what the chain ramps look like.

Could anyone give me an idea on what might be some clear indications of a bent valve?

Thanks to everyone for your replies!

[lr172]

The red bits are likely sealant. CHain ramps are dark brown or black, not red. Redarding the black, I suggest hitting them with a hammer to see how hard they really are. THe chain ramps are not your typical placstic. They are very hard and brittle. Also, you would likely see more of it if they went bad.

Finally, chain ramps do not impact timing. The tensioner keeps the chain tight on the two gears just like in ildler pulley keeps a serpentine belt tight. I don't know much about the old mechanical tensioners, but I am not sure if they are known to fail suddenly. Were these upgrade to hydraulic tensioners during the rebuild? I wouldn't be worried about bent valves. They typically create more than just an unpleasant noise in your valvetrain

However, if you suspect those black bits are chain ramp pieces, you need to start investigating. I suppose if someone left the shims out from behind a cam gear, the chain could start to eat away at a ramp.

First step is to understand what happed to your valvetrain. You should pull the chain case cover on the side with the problem if you don't find your problem under the valve cover.

The most likely cause of bent valves is incorrect cam timing. Depending upon the severity of the slip in timing, you are likely to bend many valves, if not all. In this case, the engine will run quite poorly, as it will have very little compression. It would also be very likely to backfire through the intake manifold. As I said above, don't worry about that yet. If the engine was running well and only started to make noise, you are likely to be able to find the problem and resolve it. Don't wory about anything yet but getting that cover off. You may want to pull the intake cover as well. Once you have some evidence, we can figure out the issue and THEN you can worry.

The test for bent valves is either a leakdown test or a compression test. A leakdown will show minor damage that may be missed on a compression test.

Good luck.

Larry

[T77911S]

the noise could be a rocker shaft that came lose.

that stuff looks like some kind of gasket sealer, perhaps what has glued the valve covers on.

is this guy a porsche guy?

[KNS]

So what is the best option for the original poster? Remove the covers, scrape and clean all the old sealant off (if that is ,indeed, what it is), buton back up and drive? Or, tear down the engine for a thorough cleaning?

From the chain housing area and lower valve cover areas, what would be the path of circulation of those little bits of sealant - directly to the sump screen or throughout the engine?

[leadrsa729]

Hi All -

I plan on doing my best to remove those lower valve covers after work tonight. I will definitely let you know what I find.

In regards to KNS's question - Should I indeed scrape off all the sealant that I might find? If I do, wouldn't that likely reinstate the probable leaks that the mechanic was trying to cover up in the first place? And if it does, how would I correct those leaks without going down the same sealant covered path that he did?

As always, thanks for your help!

[KNS]

leadrsa,

I think cleaning all of the (incorrect) sealant off first is more important than having to deal with the leaks themselves. The proper sealants and gaskets as well as having un-warped lower valve covers should take care of the leaks.

I raised the question because some idiot had used some silicone sealant on the chain covers on a recently purchased Carrera prior to my ownership. It is still soft and flexible - on the outside but I need to clean it off and am wondering if, after all these years, a complete teardown and cleaning is in order. That's why I had asked about the oil circulation from the chain housings and lower valve covers.

[T77911S]

the reason i asked if he was a porsche guy was that V8 guys use a lot of sealer on their motors and may have used it not knowing it was not needed. also this could make a difference on whether to rebuild or not.


i had hard sealer on my valve covers too. spent hours cleaning. the sump pan is the same way but i have not taken that off yet.

update to the turbo valve covers.

the stuff in the oil sump? one option would be to check the tensior covers and clean and reseal, change oil filter and drive for a little while, monitoring oil pressure, then pull the sump pan and check for more debris. oh, pull the drain plug on the tank and perhap pour some oil in to help wash anything out. i might even cut open the current filter to see if i could see anything in it. i might even buy a couple of purolator filters and change every 50 miles or so.

do the rebuild yourself and if he put in new bearings, reuse them. you are looking at a gasket set and sealers as far as expense.

the oil goes back to the tank, then pump and then filter

[leadrsa729]

Thanks for the advice T77911S!

He is a Porsche guy actually, which surprises me based on the experience I had with him.

I've also got the turbo valve covers already. What kind of sealer should I use on the tension covers, if any, after I've removed and cleaned them?

[E Sully]

I used a very light glaze of loctite 574 on the chain cover gaskets. Worked well for me and also on the transmission gaskets. Nothing on the valve covers. I had cleaned all the surfaces as well as I could, but still had some light leakage on the chain covers and lower transmission plate. No problems now. It was recommended to me by my local Porsche specialists. There is also a good thread on the technical forum on sealants.

[lr172]

I wouldn't be overly concerned about excess sealer debris in your oil system. Millions of engines have been rebuilt / repaired with hard and soft sealears for decades and you will always have some debris fall off on the inside. THis is why you have a screen in the sump and an oil filter. The screen is sized to only allow through particles that will not clog the oil pump.

The scavenge pump (a component of the oil pump - it has two) pulls oil to the oil tank while possibly passing the aux oil cooler. The pressure side of the oil pump pulls oil from the tank and past the filter (this is one the suction side, so the pump doesnt see it until after the filter) and then on to the oil galleries. Any material that makes it past the sump, only has to pass the scavanging side of the pump before it reaches the tank/filter which will catch it. The scavanging side of the pump is low pressure and wont have the tight clearances of the high pressure side.

This is one of the key reasons that an oil change is required 100-500 miles after a rebuild. The filter fills with miscellaneous debris including metal that wears off new components that are mating. Once full, oil bypasses the filter.

The idea that someone would rebuild an engine to elminate sealer debris seems over the top. Once you tear down the engine, how do you plan to rebuild it without using more sealers? The case must be sealed and it is not possible to avoid sealant building up on the inside of the joint.

Loctite 574 is anaerobic. It dries hard in the absense of O2 (such as your case joints after tightening. While it is initially soft at the edges of the joints, once mixed in with oil, it loses access to oxygen and cures within the oil. This is why you are seeing hard red debris.

I agree that your rebuilder probably slopped it on too thick. However, a rebuild is too extreme, given the potential for problems. If your uncomfortable, pull the sump and strain your oil every 100 miles till you feel better and replace the filter while your there.

To the poster regarding silicone, GM used silicone in place of oil pan gaskets, to save cost, for almost a decade before O2 sensors. Silicone does not have a big problem with particles breaking off on the inside. The stuff dries to a rubber consistency and requires significant force to tear it off, unllike hard sealants. It wont breakdown with heat or oil flow like some other sealants.


Good luck and let us know what you find.

[lr172]

Originally Posted by leadrsa729

Thanks for the advice T77911S!

He is a Porsche guy actually, which surprises me based on the experience I had with him.

I've also got the turbo valve covers already. What kind of sealer should I use on the tension covers, if any, after I've removed and cleaned them?

Again, I wouldn't pull the covers just to clean them. The chain case drains directly to the sump and you can clean them out there. WHen I re-did all my chain case seals, I used Permatex anaerobic, which is the same as loctite 574. I was judicious in keeping a thin coat, but still had sealant on the edges after tightening. What is on the outside edges is also on the inside edges. I am certain this is floating around somewhere in my engine. Granted my squeeze out was not substantial, but it is definately there. I am not losing sleep over this.

[KNS]

lr172,

Thanks for your post. As I had mentioned, I too, have black sealant slopped on thick on my chain covers and valve covers on a Carrera. It is still soft and flexible along the outside seams. It's a few years old according to records. I am assuming it is silicone, it looks like a permatex type product.

Unfortunately, unlike an ealier car, I can't pull the sump plate to have a look at the screen like the SC. I think on my next oil change, I will try and catch some oil in a screen as it is draining and take a look at it. I ran an oil analysis on the first oil change I had with the car. Blackstone labs returned the report saying everything looked good except a high content of silicone which they thought may be silicone sealant.

leadrsa,

I hope i didn't highjack your thread, it looked like we had a similar problem.

[leadrsa729]

Thanks for all the info guys, this really helps me out a lot.

I pulled the lower valve covers off and yes there was a lot of the black ruberry silicone sealant on them. What's a good brand of this sealant? The valves, rocker arms and springs looked good however. I have not tried to adjust them yet, or even see if they need it. I'm hoping #3 does need to be tightened down since that's where I heard the most noise coming from.

I also saw a lot of the Loctite 574 deeper inside around my exhaust valve springs. You could see red rings around them with a flashlight. Nothing around the intakes though.

After I pull the timing chain covers to see if anything looks wrong there, my next step is to perform a compression test. Anyone have any tips for pulling the covers while the engine is still in the car - looks a little tight in there!

KNS,
Don't worry about hijacking anything - all of this is good info!