timing cover questions

[1979 Quartermasters]

Good morning

I ordered a new timing cover for my 5.7 from a Merc dealer because its a plastic one time use. When it arrived, it was a metal one and the parts guy could not find the plastic one for my serial number.

So I went to the GM dealer and he used the number from the inside of the cover (125628180). The new one came yesterday and its a little different. It fits the block the same as the old one, but it has that square piece on top that the old one doesn't have. Also on the front, the old one has the number CAV13 and the new one has CAV15.



The new on is on the right.

I was wanting to install this cover this morning but I not sure if its the right one.

Does any one know?

Thanks.....

Ken

 

[1979 Quartermasters]

Re: timing cover questions

bump

 

[alldodge]

Re: timing cover questions

Looked my self but cannot find a thing as to why they are different, sorry

 

[1979 Quartermasters]

Re: timing cover questions

Thanks for the response. I was beginning to think only I could see my posts.

Any idea why my serial number would list a metal cover and it has a plastic one. I know it was repowered by the PO, but what motor had the plastic cover?

I put the cover on and all was well. The parts guy at the GM dealer said there was only one option for that number. He said it was probably an upgraded version.

Ken

 

[alldodge]

Re: timing cover questions

Thanks for the response. I was beginning to think only I could see my posts.

Any idea why my serial number would list a metal cover and it has a plastic one. I know it was repowered by the PO, but what motor had the plastic cover?

I put the cover on and all was well. The parts guy at the GM dealer said there was only one option for that number. He said it was probably an upgraded version.

Ken

I can only guess, but my only thought is do you think someone replaced the engine or had trouble before you got it? If you had it since new that would out.

 

[Bondo]

Re: timing cover questions

Thanks for the response. I was beginning to think only I could see my posts.

Any idea why my serial number would list a metal cover and it has a plastic one. I know it was repowered by the PO, but what motor had the plastic cover?

I put the cover on and all was well. The parts guy at the GM dealer said there was only one option for that number. He said it was probably an upgraded version.

Ken

Ayuh,.... Yer serial numbers are for the original Mercruiser Dressin's on the New long block is My guess,....

That's how things like this usually go,....

So long as it don't Leak,.... don't worry 'bout it,...

 

[Don S]

Re: timing cover questions

Does your serial number come from the metal tag on the block, or the decal on the carb cover?
Might want to get the GM block number and see what it crosses to.

 

[1979 Quartermasters]

Re: timing cover questions

The serial number comes from the tag which looks like it was removed from the old engine and attached to this one above the starter where it's supposed to be. It's the same as the one on the arrester cover. It's in my signature.
Where would I find that block number. I'll find it in the morning and post it.

Thanks.....

Ken

 

[RogersJetboat454]

Re: timing cover questions

The serial number comes from the tag which looks like it was removed from the old engine and attached to this one above the starter where it's supposed to be. It's the same as the one on the arrester cover. It's in my signature.
Where would I find that block number. I'll find it in the morning and post it.

Thanks.....

Ken

Facing the engine it would be on the right side cast into the block right where it meets the flywheel cover.

Spot #3 on this diagram;

 

[Bondo]

Re: timing cover questions

Facing the engine it would be on the right side cast into the block right where it meets the flywheel cover.

Spot #3 on this diagram;
View attachment 203715

Ayuh,.... That's the Castin' numbers,...

Just ahead of the starboard head on the block's deck, there Maybe stamped numbers 'bout it's manufacture, if it ain't been decked,...

The Upper spot #4,...

 

[Don S]

Re: timing cover questions

I would like the block casting #, #3 in the drawing.

That engine serial number was made in 94. The composite cover didn't exist then as I recall.

 

[1979 Quartermasters]

Re: timing cover questions

There is a tag on the side of the block saying it was bored.030 over and some other numbers in regards to the rebuild. The date on that tag is 2006. I guess that wouldn't suggest anything about the origin of the block.


Ken

 

[RogersJetboat454]

Re: timing cover questions

There is a tag on the side of the block saying it was bored.030 over and some other numbers in regards to the rebuild. The date on that tag is 2006. I guess that wouldn't suggest anything about the origin of the block.


Ken

Nope. And chances are good when the refurbed the engine, they decked it to clean it up removing the GM suffix code Bondo was speaking of.

If you get the casting numbers from the spot I posted, it should reveal what era that block was used.

 

[1979 Quartermasters]

Re: timing cover questions

Thanks for all the replies.

I took a picture of the area I believe to be #3. I hope this helps.



Thanks....

Ken

 

[alldodge]

Re: timing cover questions

Looks like it will be on the starboard side

 

[RogersJetboat454]

Re: timing cover questions

Thanks for all the replies.

I took a picture of the area I believe to be #3. I hope this helps.
Thanks....

Ken

Block casting number not there, BUT I059 is a casting date.

September 5th 1999

 

[1979 Quartermasters]

Re: timing cover questions

How about this one...14093638.

Ken

 

[Don S]

Re: timing cover questions

The casting date tells the storyl. You won't have a 99 engine in a 95 boat.

In your picture you can also see a round shiny disc with orange glue, on the back of the head. That is an overheat detector put on by the engine rebuilder. My guess is the long block was replaced with perhaps a Merc reman (Thus the tag for .030 bore). Most engine rebuilders go .060 and never measure. Merc only recommends max of .030 bore.
They probably also sent some rivets to put the old tag on the new engine so you knew what all the accessories are.
In 99, the composite timing cover was in use.

 

[alldodge]

Re: timing cover questions

How about this one...14093638.

Ken

And the winner is 14093638...350...87-95...2 or 4...Roller or flat tappet cam, one-piece rear seal

 

[RogersJetboat454]

Re: timing cover questions

How about this one...14093638.

Ken

OK...

Here's where it gets weird...
Casting number above (from a few separate sources) decodes as;

Casting#---CI---Years---Main----Camshaft---------------Rear main seal
14093638...350...87-95...2 or 4...Roller or flat tappet cam, one-piece rear seal

Going by that info, that date code would be more likely September 5th, 1989....
Date codes tell you the month, day, and last digit of the year, but not the decade.
Thing is though, they didn't have the plastic timing covers back in 89, they were still using the stamped steel covers (hence why I concluded 99 rather than 89).
The blocks used for the steel covers, and the plastic covers are physically different from each other.

I'm still thinking this is a '99 block, since it had a plastic timing cover. GM may have re-used the casting number (modifying it for Vortec engine use) with out the different interweb sources of casting info out there picking up on it.