99 Vortec timing cover and gasket question

Hi all-I'm thinking of changing timing cover as I have a bit of a leak and I have few questions:
1.anybody used Pioneer or ATP cover-what's your opinion on them?
2. Do they come with gasket or do I need separate gasket?
3. If yes to question 2-then is it 1st design(58mm) or 2nd design(61.5mm) on 98 tahoe-?
4. Does the crankshaft seal need to be replaced or is it "built in" into a cover?
5. I also looked into Holley cast aluminium cover but opinions on it are not so great on summit-anybody used it?
Thanks in advance

1.anybody used Pioneer or ATP cover-what's your opinion on them? Pioneer many times, no issues.
2. Do they come with gasket or do I need separate gasket? Came with gasket preinstalled.
3. If yes to question 2-then is it 1st design(58mm) or 2nd design(61.5mm) on 98 tahoe-? Couldn't tell you on that one. I've always bought those local and I've never had an issue.
4. Does the crankshaft seal need to be replaced or is it "built in" into a cover? Preinstalled as well.
5. I also looked into Holley cast aluminium cover but opinions on it are not so great on summit-anybody used it? Nope, I'm a cheap basta... I mean a frugal man.
Thanks in advance
You're welcome

Dariusz Salomon said:

Hi all-I'm thinking of changing timing cover as I have a bit of a leak and I have few questions:
1.anybody used Pioneer or ATP cover-what's your opinion on them?
2. Do they come with gasket or do I need separate gasket?
3. If yes to question 2-then is it 1st design(58mm) or 2nd design(61.5mm) on 98 tahoe-?
4. Does the crankshaft seal need to be replaced

You must be registered for see images attach

or is it "built in" into a cover?
5. I also looked into Holley cast aluminium cover but opinions on it are not so great on summit-anybody used it?
Thanks in advance

Click to expand...

When I replaced the timing cover on my other 99 vortec Burb, I used a factory GM one. Didn't have the aftermarket ones yet(this was in 2007). IIRC it came with the crankshaft seal installed. The gasket set was separate. You'll need the 2 water pump gaskets too, they should be in the set for the timing cover replacement. The original cover is plastic, and they do eventually warp and leak. That's why GM recommends replacing the cover when the timing chain and gears are replaced. That's what I was doing on that Burb (started out as an oil change and replacing the belt idler pulley, got more involved quickly when the water pump was leaking). I personally haven't had any experience with the metal covers for the vortec engine.

I replaced mine on my 1999 5.7 Vortec earlier this year and the new one had the seal already in it and the gasket was a bead of silicon already applied. The only other thing supplied with it was a bolt for the CPS and (IIRC) a small amount of silicon sealant (see below). That (and water pump gaskets bought separately) was bought in the UK from US Automotive - and was £80+.
Remember that whatever cover you use, it must have provision for the CPS and be spacious enough to clear it's trigger wheel.

Think about the sump/oil pan gasket as recommended fitting procedure is to lower it at the front and reseal with silicon sealant to the timing cover. If the gasket tears a new one is required along with complete removal of the sump/oil pan.
The harmonic balancer also has to be removed and re-fitted. Tools are required for this and you'll also need a method of holding the fan to remove it from the pump.

I did all of that before I joined this forum and since, I think, I have read that the timing cover can be replaced without disturbing the sump - others can advise on this.

Thanks fellas-that's helpful. Pinger what brand was your timing cover-do you remember?
HotWheels-I don't think factory ones are available anymore-nor summit or rockauto has them. Will look on ebay but I don't hold my breath.

HotWheelsBurban said:

When I replaced the timing cover on my other 99 vortec Burb, I used a factory GM one. Didn't have the aftermarket ones yet(this was in 2007). IIRC it came with the crankshaft seal installed. The gasket set was separate. You'll need the 2 water pump gaskets too, they should be in the set for the timing cover replacement. The original cover is plastic, and they do eventually warp and leak. That's why GM recommends replacing the cover when the timing chain and gears are replaced. That's what I was doing on that Burb (started out as an oil change and replacing the belt idler pulley, got more involved quickly when the water pump was leaking). I personally haven't had any experience with the metal covers for the vortec engine.

Click to expand...

Is replacing a chain recomended-I know some modern vehicles need them as they stretch and all but I didn't think 350 needed it?

Dariusz Salomon said:

Thanks fellas-that's helpful. Pinger what brand was your timing cover-do you remember?
.

Click to expand...

Can't remember other than it appeared to be identical to the one that came off ( including 'made in China' marking). I have no idea if the one I removed was original though. It also had a set of new retaining bolts - forgot thought earlier.
Tried to find it on US Automotive's web site but not listed. They ordered it from USA. I still have the old one and I'll have a look at it later for any clues as to who made it - and the box the new one arrived in if it's in the garage that is (binned more likely).

Where is yours leaking from (and before going further - is your PCV good as that can be a cause of a leak)?

Seeing as you're in the UK, I'd want to keep the truck tip-top because parts aren't as easy to come by, so I'd replace the timing chain.

If you're replacing the whole timing cover, what do you care about the outside diameter of the seal? The inner diameter is going to be the same, unless anyone knows of a different diameter harmonic balancer and has failed to mention it.

How many miles/kilometers does your truck have? My other Burb had around 175,000 miles on the 5.7 vortec (350) when I did the timing job on it. My memory isn't clear because it was 13 years ago LOL.
Current Burb has 191,000 and still original inside the engine. Runs great, so don't think it's due yet. Maybe in the spring, when I should hopefully have a daily driver vehicle besides it. Coming up on 200,000 miles though, there's several things that will need doing in the near future.
On mine I did drop the oil pan to get the cover off. It was leaking, but it was a major part of why this job took 3 weeks instead of just one weekend. And both my Burbs are 2wd so there's a little more room than on the 4wd model. Still not a lot though! Another reason I miss my square body Burbs.....
If there's a way get the TC off w/o dropping the oil pan, that's what I would like to do on this Burb. The oil pan doesn't leak, and I'd like to keep it that way!

HotWheelsBurban said:

On mine I did drop the oil pan to get the cover off. It was leaking, but it was a major part of why this job took 3 weeks instead of just one weekend. And both my Burbs are 2wd so there's a little more room than on the 4wd model. Still not a lot though! Another reason I miss my square body Burbs.....

Click to expand...

This is what I'm trying to get across. Aware also that on a 4WD (which I think the OP's is) it's worse still.

HotWheelsBurban said:

If there's a way get the TC off w/o dropping the oil pan, that's what I would like to do on this Burb. The oil pan doesn't leak, and I'd like to keep it that way!

Click to expand...

Haynes suggests loosening bolts and lowering the pan but add that if the gasket breaks..... (as mine did). I wasn't too bothered as I wanted a look inside after the pop but I'd be in no rush to remove the pan again unless I had to. Organising tools for the harmonic balancer (off and on) took time as well. It's a job that looks easy from a distance but is pretty onerous once stuck in.