Sump Gasket Question

I am chasing a metallic tick in my engine as some have described and frustratingly, no joy so far. I have replaced the rocker shaft, ensured all the rocker arms were not dished, inspected the push-rods to see if any were bent and even replaced the tappets looking for the noise. As a note, one of the tappets was cracked across three of the upper holes! I bore-scoped the cam while I had the tappets out and did not see any obvious flat spots. The noise sounds like valve lash but I have adjusted the valves many times and no change.

Today, I pulled the oil pan to be sure nothing was in the pan and as I suspected, nothing! Not even very much sludge in the bottom!

Now I am preparing to re-install the pan and have a couple of questions. I pulled the square filler at the front bearing cap and have replaced it. by driving the new cork spacer into the block with a little grease as a lubricant The new spacer is not flush with the block. Is this correct or do I need to try to trim it flush? Also, I have read many posts on gasket sealant and am still not certain which to use. I have Permatex Ultra Black that I bought for it's oil resistance. Is this what i should use on both sides or as some say, should I use it on the pan side and blue RTV on the block side?

Timing chain? Although I have a 4 cylinder engine I sometimes hear a very intermittant metallic tick noise. It seems that the only thing it can possibly be is a random touch of the chain to the cover. One of these years I'll get around to pulling the cover and replacing some parts. It is only apparent at idle.

When trying to pinpoint the source of engine noise I have sometimes used a long screwdriver, touching the metal tip to various parts of the engine while holding the plastic end to my ear. Other times I have used a long piece of tubing as a stethoscope. Have you tried using anything like this? type of aid

Use either on both sides, I prefer black.

Thanks Larry!

Richard,
I have a stethoscope I have been using to try to find the source. I thought I heard something near cylinder 35 tappets which led me to pull them and found the cracked tappet but replaced and no difference. While I have the pan off, I did my best to inspect the rod ends for any indication of looseness and cam lobes. Again, nothing obvious as far as anything loose or flat spots so the mystery continues but more and more looking like an engine rebuild is in my not-too far off future!

Any suggestions on the cork spacers not being near flush to the block?

If you are talking about the square cork gaskets that run across the front & rear main bearing caps (shown on the Moss drawing as part of the gasket set #54 and next to the round felt plugs for the main caps #13) - do not trim, they will crush and seal when the pan is bolted up tight.
Dave

My metallic clicking sound ended up being broken piston ring on top of piston. Compression test did not reveal this nor did a stethoscope. Can you bore-sight it?

Thanks Dave. I had to drive them into the slot with a punch and hammer so was not sure it would ever compress enough to seal. The cork seal is probably about 3/16” proud of the block. Does that sound consistent with being able to compress? I plan on adding a healthy glob of gasket maker around there to be sure I can get a good seal.

Patrick, I have borescoped the bore and last time, I did not see anything. I plan on looking again before I get everything back together this week.

Dave, I think it is more like 1/8” proud, not 3/16”.

Doug, 1/8" proud is about normal and should compress enough for the main gasket to seal - these sit right at the edge of the gasket surface on the pan where there is a healthy radius, so it is filling a sort of triangle shape cross section with the radius being one side of the triangle so it doesn't completely compress. It sounds like you have it but if you feel the need to try getting it further in, I suggest using something fairly wide, thick & blunt to drive it with so you don't just cut into it such as a short piece of 1/8" x 1" flat bar. Again, if it's only 1/8" proud, it should be fine (liberal gasket sealer use authorized).
Dave

Thanks Dave!

Doug--

If you have not already done so check the sump to see if there is any distortion/dent as there is very little clearance between the crank throws and the pan interior. Once when I was driving my ex-wife's BN7 I ran over a small object that apparently dented the pan and caused a loud clicking sound which varied with RPM'S. On dropping the pan I found the dent which I easily banged out with a ball peen hammer while holding the pan against a sandbag.

Everyone has their favorite sealant and for the pan I use ultra gray or black though the application and tightening technique is probably more critical than the product used.

Doug, I have been using Ultra Black for years but the last time I put a rear end cover/case together or the rear pumpkin in the housing, I used what is commonly called "Utra Green". The correct name is Permatex Gear Oil RTV Gasket Maker. It may be overkill for the engine pan as it is formulated for gear oil applications but if I was to use anything other than Utra Black it would be the green. From what I read the ultra gray sets up a little harder than the black and is intended for machined surface parts that are not intended to move at all. The green seems a little more pliable than the black.

Hey Tex BJ8, Does engine tick increase or decrease with RPM, at idle or while driving under load? Has it developed over time or suddenly? Any misfires or engine-running issues? Overheating or overheated? Have you tried running engine briefly without fan belt to isolate other rotating bits such as Generator or Water pump. Suggest inspecting harmonic balancer / pulley. Delaminated HBs could make all sorts of noise which tend to emanate elsewhere in the engine.

Gonzo,
The tick follows engine speed. It has developed over the last couple of years and is a consistent sound. The engine runs great although one cylinder is about 30% lower compression than the others. Interestingly, I did a leak-down test a couple months ago and all were similar and in the green on my gauge (I don’t have the actual values handy). I have run the engine without the fan belt and no change. It has never over-heated in the 30+ years I have cared for her. I have pulled each individual plug wire trying to see if I could isolate a piston slap or wrist pin knock and again, no change in the noise. I will look more closely at the harmonic balancer but I was under it this week listening to the engine run and did not see any wobble or hear anything knocking in the pan or HB area. I have also tried to inspect for exhaust leaks and did not find anything obvious.

i really appreciate all the thoughts as I keep hoping I can postpone a rebuild a couple more years!

I had a similar sound on another car, and it was loose exhaust manifold nuts.