Problem with Silver Seal front covers

Paul Lohr

Member
Joined
Jun 11, 2010
I bought a Silver Seal front cover back in October. Long story short, the cam sensor bore is not aligned with the oil pump shaft bore. The components can be assembled in the cover, but as you could imagine, the cam sensor and oil pump drive gear eventually bind as they are turned. I sent the cover back to Silver Seal so they could check this problem. They agreed that the cam sensor and oil pump drive gear bind in the timing cover and that this is a problem with the timing cover. They also checked numerous other front covers they had in stock - all had the same alignment problem. But Silver Seal still sells the defective front covers without any disclaimer. I'm out the time and money on this front cover. Obviously I do not want another defective front cover and they will not issue a refund. I did modify the oil pump passages, and this has become the excuse for not issuing a refund. I have worked in the retail performance industry. Never did we use such an excuse to pinch someone.

My GM timing cover has the same alignment issue. I've heard this is common. This is the likely excuse used by Silver Seal - the front cover is to the same specifications as the GM front cover (with one big caveat). It is no wonder why these engines end up with low oil pressure, with the oil pump drive gear wobbling in its bore and wearing the aluminum surfaces quickly and unevenly. Surprisingly very little has been spoken of this problem on this forum (from what I could find).

Obviously I need to find a front cover that does not have this alignment issue. I called TA Performance to ask if they have corrected the alignment problem that plagues the GM and Silver Seal front covers. I never got a straight answer. Not even sure the lady answering the phone understood the problem. They did not allow me to speak with someone who understood the problem...might have been the secretary who answered the phone? She was polite and friendly, she just did not have an answer. I'd like to hear about the experiences others have had with various front covers related to the cam sensor / oil pump bore alignment.

Sorry for the negativity. Hopefully someone else can learn from this.

Paul Lohr
 
Paul,

I feel for you.
I gave the choice of front covers alot of thought before I replaced mine this winter. Did a bunch of research & read plenty of posts about this type of problem & more. Ended up going with a TA front cover (replaced the oil pump gears & set clearances). The cover only req'd minimal oil passage clean up ........overall I must say it is a pretty impressive cover. Also installed new TA Billet Steel Timing Gear Set with chain while I was in there.

Although I haven't fired up the motor yet, it is now fully assembled and oil pump has been primed. When checked visually, the cam sensor bore seemed to be aligned properly with the oil pump gear passage and there doesn't seem to be an apparent binding that could be noticed (in fact it did seem to be turning quite smoothly). I had heard or read somewhere that TA Performance had corrected the original misalignment issue found on many aftermarket covers. I'm not sure whether they accomplished this in their casting design, or if it was done in the machining process afterwards?

Suggest you call TA Performance back and speak with Mike Tomaszewski (you can reach him on this board too.....TABuickMike) as he would know the answer to your original question. Otherwise, I would ask Nick Micale about his experiences with this issue.

Dave
 
These issues are well known and have been posted about many times. Fixing the issue is not worth the time. Source a good used cover or get a new assembly from TA.
 
Be aware there are some defective COMP camshafts out there too with incorrect thrust face thickness machining. This defect places the camshaft too far forward in the engine and puts the cam gear out of alignment with the cam sensor bore.

I've encountered it on a cast roller cam myself.
 
The TA cover is the best out there right now...Best meaning the tolerances in the oil pump for one and of course everything else lines up as it should.

FWIW....I purchased a Brand new GM cover last year for my new build and new out of the package the oil pump cavity was outside of GM's own max spec, so they sell a new part that doesnt even meet there own specs......FAIL...

Get the TA
 
Be aware there are some defective COMP camshafts out there too with incorrect thrust face thickness machining. This defect places the camshaft too far forward in the engine and puts the cam gear out of alignment with the cam sensor bore.

I've encountered it on a cast roller cam myself.
I've seen this. I cut the cam thrust in a lathe and it was gtg.
 
I've seen this. I cut the cam thrust in a lathe and it was gtg.

How does one check for this? I just slid a new cam into mine (unknown manufacturer), and I'd like to chech it.
 
Can you explain the binding issue a little better? Can the pump gears be turned inside the front cover with the oil filter housing on and without the cam sensor installed? What are your clearances? Some runout of the oil pump gears seems to be common and doesn't mean there is a problem with the cover. I don't know if this is the problem or not, but another idea you may want to check. There shouldn't be a huge problem with the GM cover. They have proven themselves in tens of thousands of cars.
 
I'm really not surprised to learn there is a problem with an aftermarket timing cover. As already mentioned, problems with them have been noted before. I can truly appreciate your sincere effort to warn others of a binding problem with the Silver Seal. I've never seen a Silver Seal timing cover, so I'll take your word for it. But since you have noted the same exact problem with a factory GM cover, and are unconvinced that TA Performance and has remedied the problem on their cover, what are we going to use? I am also left to wonder how the problem can be as bad as you perceive when all of the GM cars using this same factory timing cover lasted for the combined millions of miles if the oil pumps aren't working correctly as you have noted. I'll bet most of the low oil pressure problems our engines experience are caused by excessive bearing clearances rather than defective factory GM timing covers.
 
I'm really not surprised to learn there is a problem with an aftermarket timing cover. As already mentioned, problems with them have been noted before. I can truly appreciate your sincere effort to warn others of a binding problem with the Silver Seal. I've never seen a Silver Seal timing cover, so I'll take your word for it. But since you have noted the same exact problem with a factory GM cover, and are unconvinced that TA Performance and has remedied the problem on their cover, what are we going to use? I am also left to wonder how the problem can be as bad as you perceive when all of the GM cars using this same factory timing cover lasted for the combined millions of miles if the oil pumps aren't working correctly as you have noted. I'll bet most of the low oil pressure problems our engines experience are caused by excessive bearing clearances rather than defective factory GM timing covers.

The original GN covers were manufactured over 25 years ago, and as the GM original parts supply ran out they again go to vendors to make additional parts. It may or may not be the original supplier?

We do know many aftermarket, and many OEM parts are being produced off-shore. In recent years Silver Seal, Dorman and other suppliers have been well known to have problems with their Buick timing covers because of poor machining quality overseas.

After dealing with hundreds of timing covers, I have never seen a problem with a stock, unopened turbo cover/pump, some even running in the 9's.

When the GM supply of V-8 Buick covers was exhausted, TA cast and built a better replacement.

The similar situation came about with the V-6 cover, and the aftermarket had extremely poor quality, TA again stepped up and did a replacement cover.

Being involved in that project, I do know that TA made many changes and improvements, the most important being closer machining tolerances than the original GM cover, especially in the critical area of the pump cavity.

So it comes down to the point that when replacing a turbo V-6 cover, either find an original GM turbo cover, or use the TA piece for trouble-free installation and performance. :)
 
As far as I know, most of the NOS GM covers on the market today are made by the same American OEM company that originally made them. I found several hundred of them in a warehouse a few years ago (in storage since the mid 90's) and sold them to various Buick vendors out there. If anyone can build a "better mouse trap", TA Performance can. Until I see an independent A-B comparison test, I will reserve judgement which actually performs better out of the box. I think you would be safe using either one without any serious issues such as "binding".
 
Pioneer had this problem so bad the shaft wouldn't mesh with the cam gear and wouldn't even seat into the bore, but they did correct it a few years ago. They said it had to do with machining outsourced to China.
 
The original GN covers were manufactured over 25 years ago, and as the GM original parts supply ran out they again go to vendors to make additional parts. It may or may not be the original supplier?

We do know many aftermarket, and many OEM parts are being produced off-shore. In recent years Silver Seal, Dorman and other suppliers have been well known to have problems with their Buick timing covers because of poor machining quality overseas.

After dealing with hundreds of timing covers, I have never seen a problem with a stock, unopened turbo cover/pump, some even running in the 9's.

When the GM supply of V-8 Buick covers was exhausted, TA cast and built a better replacement.

The similar situation came about with the V-6 cover, and the aftermarket had extremely poor quality, TA again stepped up and did a replacement cover.

Being involved in that project, I do know that TA made many changes and improvements, the most important being closer machining tolerances than the original GM cover, especially in the critical area of the pump cavity.

So it comes down to the point that when replacing a turbo V-6 cover, either find an original GM turbo cover, or use the TA piece for trouble-free installation and performance. :)
So the TA cover is cast by them? That's awesome if it's true....I'll have to try one in the future.
 
WE2Regal: With one of these front covers that misaligns the oil pump drive gear and cam sensor, how many miles will the engine go before oil pressure at hot idle has dropped off dramatically? Perhaps someone knows the answer to this, I do not. How much damage will the tiny aluminum particles in the oil system do to other components in the engine? I can't say. Not sure anyone wants to perform this test.

The GM front cover has been mentioned a few times. If someone uses a GM cover, please check the alignment of the cam sensor and oil pump drive gear. Perhaps there are GM front covers that have proper alignment?

Nick: thank you for the recommendation of the TA front cover. That is the one I will end up using.

Paul Lohr
 
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