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I'm doing the timing chain on my 1979 Eldorado with 350 or 5.7L Oldsmobile engine (factory original for that year) which requires removal of the balancer and the front cover.

Almost everyone has an issue trying to install the timing cover with a new lower oil pan to cover gasket. A friend who has had a lot of Oldsmobiles and was also a dealer mechanic mentioned a trick to me which I finally had a chance to try and so I wanted to share it here as, out of curiosity, I searched and found a lot of discussions but none where this method was used. Everyone recognizes the issue though and solutions like lowering and disturbing the front of the oil pan seal were suggested in the threads I came across.

Instead of using the new lower seal in the kit throw it away or put it in your tool box and use the OLD seal. The old seal is perfectly deformed to fit. It needs to be cleaned very well, while still installed, and you do need to use a thin layer of RTV on the oil pan lip but, once done, the seal fits very nicely and because of the dowel pins the geometry of the seal/pan and the motion of install works very well. This method makes a common problem a non issue.

I did also notice that the original oil pan side gaskets extend into the area where the front lower seal goes so I also trimmed that back so there was no "tongue" of the pan side gaskets sticking into that area. I took a photo of that area so at some point I will show it to clarify what I mean. I trimmed it because, regardless of new or old lower seal, that area relies on some RTV and so it was best to not have that extra flap which could have interfered with the RTV.

Regarding which RTV I normally select Permatex. They have a recommendation for most situations and for any situation which will frequently be in contact with oil they recommend their "Ultra Black" so that's what I used.

After cleaning everything thoroughly I wiped all surfaces down with acetone. As mentioned apply a thin layer of RTV to the oil pan lip and then a more generous application in that corner area including the bottom of the engine block casting in the same area as the seal ends.

One thing I firmly believe I should have done and I still regret not doing was adding a little RTV to the bottom of the 3-sided main cover gasket. I believe it will be difficult for the lower seal RTV to get to that area, the 3-sided main seal ends there and there are a lot of surfaces coming together at that point. I thought about taking it apart but the problematic lower seal looked perfect and I did goop the top of the area where the lower seal goes quite well; the thought being maybe the lower seal squeezed some RTV in that area of the main cover gasket anyway. If I did it again I would add a little at the bottom of the paper front gasket.

BTW: Permatex recommendation for best performance in areas seeing frequent engine coolant EG is their blue.

RTV/Gasket question for others:
What are people using for the main front cover gasket and water pump gasket? Any RTV or none?

I tried to find a FelPro recommendation for their paper-blue gaskets. They seem to have a recommendation on all of their new tech but I found nothing on their classic blue-paper gaskets. In general, not specific to this application, people seemed to be favoring no RTV.

I had to use at least "Hi-tack" so the gasket would stay in place during vertical assembly. I started by placing the gasket on the front of the engine but I found that was a mistake. The exact intended location was too vague and, despite dowel pins and some very obvious geometry, the gasket was bunching. I recognized it and I then placed it first on the front cover which made it very obvious and the bunching was eliminated.

Harmonic Balancer:
Mine was well worn in the snout area by the front cover seal and it was obviously leaking oil in that area. I decided to buy a new balancer as opposed to using a repair sleeve I read was available.

I had a removal tool but not an install tool. I was able to borrow the PowerBuilt tool from AutoZone (I believe the nr was 648637). It's a tool which has fully engaged threads (in the crank area) before you make the first turn of the flange-nut which draws the balancer on. My opinion based on this one case is it is a perfectly designed tool for this job. Amazingly easy. The thread for the Olds cranks is 3/4" and a fine thread (cannot recall the exact pitch). Any similar tool with that size thread should work though.

Timing indicator:
We have a plastic part with a metal insert under the fastener. Those very often break. Mine was cracked. I looked for a metal version, common on older Olds engines, and I found one but I can see the metal versions have two bolt holes and one has a surrounding flange which I believe will interfere with the strange engine brackets on the 79 Eldorado, Toronado and Riviera. The crack in my original can likely be repaired. That part is basically unavailable. I think I will at least try to trim that earlier metal version I found from Inline Tube to see if it will work for reference.

More to follow and it would be interesting to know what others have had success with regarding the main cover gasket; RTV or no RTV.

Timing set:
RockAuto has the WRONG PNs listed for their double roller timing chains under 1979 Eldorado 5.7L gasoline. All of the double rollers listed for the 79 Eldorado are SBC PNs and those will NOt work. If you want a double roller you need to look under 1979 Toronad instead. The PN set I used was Melling "Mel-Gear" 40409. I also used assembly lube and before installing I made certain that the oil passage plug on the passenger side oil galley was clear.

My original large gear, the one mounted to the cam, had nylon teeth and several teeth had some nylon chipped off. It still ran very well but the chain had quite a lot of play and it was time to change.

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