Single upper timing chain - Late VR?

[Toad 0]

Good evening...

 

My VR was always rattly, and I always assumed that the tensioner needed replacing. Eventually last year something broke, and the rattling was very pronounced for 5-10 seconds when it would die down a bit. I decided that this was probably a good time to stop driving the car. I'd done a bit of work on her, but hadn't really experienced the vr before so didn't really know what to look out for. Been lucky enough to work on several of them since and am a lot more sure of my way round them.

 

Anyway, I decided to have a quick look at my car today. It's been parked up ever since while I've been collecting bits ready to rebuild her. I pulled the tensioner bolt out expecting to find that the seal had gone, instead I actually found a mk4 tensioner bolt, with a slightly wonky looking end and strange wear marks. I assumed that someone had fited the wrong bolt, but after sticking my finger in the bolt hole found a mk4 pad. I then pulled the inlet and rocker cover off and found this....

 

 

The rattling turned out to be the front guide broken into several pieces, and the chain slapping on the upper cover. But, why have I got a single chain? As far as I know the single upper chain was only fited to very late OBDII 2.8 VRs? The car was one of the last corrados built, but I don't think it was late enough to have one of these later tensioner setups fitted?

 

I guess that it was fitted with a late 2.8 engine, but need to find the engine code to be sure. The block has been painted fairly recently by the looks of things, probably when the chains/tensioners were replaced (the chain/bolt are both non original parts) and/or the engine was installed.

 

Are there any advantages/disadvantages to the single chain? And if it's a 2.8, how much power will I lose?

 

Cheers!

[tonedef 9]

Not sure I can answer too many of your questions, maybe even pose some more, but you say your's was one of the last VR6s, when was it built? Mine has 18/5/95 on the label in the boot so pretty close to the end and has a duplex chain for sure, see pic of head on very scruffy bench!

[dr_mat 0]

I guess that it was fitted with a late 2.8 engine, but need to find the engine code to be sure. The block has been painted fairly recently by the looks of things, probably when the chains/tensioners were replaced (the chain/bolt are both non original parts) and/or the engine was installed.

 

Are there any advantages/disadvantages to the single chain? And if it's a 2.8, how much power will I lose?

 

It might just be that someone replaced your dual-chain setup with a single-chain one when they replaced the chains. I don't think it really matters either way. Sounds like the single-chain setup fails just as annoyingly as the dual-chains do.

 

But if it IS a full 2.8 block with 2.8 cams and 2.8 inlet manifold it's 175 bhp iirc. The biggest difference is the inlet manifold iirc, and I've heard mixed reports that they might have different cams too.

[Supercharged 2]

Weird! - I'd find the engine number and code first....

 

VW changed alot of VR lumps under warranty and say this was changed in 98/99, it may have got the newer tensioners as all replacement VR's not come with the MK4 parts... still would expect it to be duplex tho...

[Toad 0]

Not sure I can answer too many of your questions, maybe even pose some more, but you say your's was one of the last VR6s, when was it built?

 

I believe from various stickers I found in it, she was built in Novermber 95 (registered Jan 96)

 

It might just be that someone replaced your dual-chain setup with a single-chain one when they replaced the chains. I don't think it really matters either way. Sounds like the single-chain setup fails just as annoyingly as the dual-chains do.

 

But if it IS a full 2.8 block with 2.8 cams and 2.8 inlet manifold it's 175 bhp iirc. The biggest difference is the inlet manifold iirc, and I've heard mixed reports that they might have different cams too.

 

Yeah I wondered if they did that too, I'll have to snuffle the code out. I *think* its a corrado inlet, the throttle body is the type without a wedge on it, so I am guessing it's all corrado.

 

I've got a set of 263 cams to fit, so if the cams are different between 2.8s and 2.9s that difference will be eliminated.

 

Weird! - I'd find the engine number and code first....

 

VW changed alot of VR lumps under warranty and say this was changed in 98/99, it may have got the newer tensioners as all replacement VR's not come with the MK4 parts... still would expect it to be duplex tho...

 

Apparently they went to single chains in 1997. Just phoned the dealer, but didn't get to speak to the freindly fellas I normally do. I'll try to pop in for a dialog report to see if there was anything that came up then.

 

I'm leaning toward getting the chain guide and fitting it (only need to remove the upper cover for that, and a new tensioner bolt and seeing how the engine runs.

[mrbeige 0]

I'm leaning toward getting the chain guide and fitting it (only need to remove the upper cover for that, and a new tensioner bolt and seeing how the engine runs.

For now....... :norty:

[Toad 0]

I'm leaning toward getting the chain guide and fitting it (only need to remove the upper cover for that, and a new tensioner bolt and seeing how the engine runs.

For now....... :norty:

 

Indeed... Keep all the shiny bits to build up a nice 2.9, maybe a bit more ( ;) ) next year. Then I'll have a little bit of cash left over for the 16v MOT in January.

[Kevin Bacon 5]

The engine code is on the block above above and to the left of the water pump pulley. I'd scrape the paint away and see what the number is. If it's AAA, it's a defo a 2.8.

 

I'm leaning toward a replacement engine at some point in it's life, from a Golf.

 

In terms of power, you'll barely notice anything tbh.

 

2.8 and 2.9 cams are identical, except in the US market. Very late ones had assymetric cams to assist cylinder filling in the rear bank.

[Supercharged 2]

The engine code is on the block above above and to the left of the water pump pulley. I'd scrape the paint away and see what the number is. If it's AAA, it's a defo a 2.8.

 

But then it could be an AAA bored to 2.9... how can you tell without lifting the head?

[Kevin Bacon 5]

Yeah that's entirely possible, hence all the simplex chain gear. The 82.5mm overbore pistons for 2.9s are notoriously difficult to get hold of. In many cases it's easier to just get new 82mm 2.9 pistons from VW to rebuild a 2.8 with.

 

Well, you could drop the sump and measure the bore with a micrometer?

[CorradoVR6-Turbo 0]

early engine numbers are as were Kev said but later ones are at the rear of the block face on the chain side,close to the intermediate shaft cap.

[Leonard 0]

I remember at the last Stealth RR day the Highline VR6's with the later management were making almost the same power as the Corrado's ie late 180's. So doubt you will notice too much.

[CorradoVR6-Turbo 0]

im now 2.8...have i noticed,heck no..lol! but thats FI!

 

As long as you have all the 2,9 bits bolted on you wont notice a thing.

[Toad 0]

Well, you could drop the sump and measure the bore with a micrometer?

 

Excellent plan! Gonna try that. You still got an oil pump for sale?

 

early engine numbers are as were Kev said but later ones are at the rear of the block face on the chain side,close to the intermediate shaft cap.

 

I looked in both locations, and while there was two 10s stamped near the intermediate shaft, there were no engine codes :(

 

What I did notice was that the black paint looks a bit too factory... And there is a white 'K' painted on the water pump end of the block. Seems odd that a DIYer would paint that on??

[CorradoVR6-Turbo 0]

when i bought my new block it also had a "k" painted on....?

[Toad 0]

when i bought my new block it also had a "k" painted on....?

 

Wonder if mine was a new block fairly recently then? Doesn't really explain the weepy head gasket and chains/tensioners being replaced... Unless mine was a short engine and they built it up with pattern parts?

 

Do you have a code on your new block James?

[CorradoVR6-Turbo 0]

never looked mate,there was something on the side but dont think it was anything...soz.

[Toad 0]

Nevermind.

 

I think I'm going to make the executive decision that the engine is a 2.8 until I find anything that proves otherwise.

 

Going to fit a new chain guide, new tensioner bolt and get the old girl running again. See how it sounds. Will drop the sump and have a ferret in there too. Need to move the car as some cattle are coming in to live at the end of the month, so I think I'll try to rent some space off a neighbour for a month or two. I'm going to leave all the shiny stuff I've bought/am going to buy off the car and get all the rest sorted asap.

[CorradoVR6-Turbo 0]

does your motor have a three bolt mount on the side of the engine were the code should be?

like this above the pump on left..

 

 

this was on the back of my block...when it was born...ahhh!

 

[Toad 0]

does your motor have a three bolt mount on the side of the engine were the code should be?

like this above the pump on left..

 

this was on the back of my block...when it was born...ahhh!

 

Yup.

 

 

:)

[CorradoVR6-Turbo 0]

i woud say it would be a newish block if you can still see all that as with the mount for later cars etc.

[Toad 0]

Most of the thread holes are clean too.

[Toad 0]

James, just been looking at your thread again and found this pic...

 

 

I assumed the number would be on the flat surface nearest the camera, but it looks like yours doesn't have the code there either. However it does look like you have a couple of random numbers like I do.

[tonedef 9]

Not sure I can answer too many of your questions, maybe even pose some more, but you say your's was one of the last VR6s, when was it built?

 

I believe from various stickers I found in it, she was built in Novermber 95 (registered Jan 96)

But that would mean it was built five months after they stopped building Corrados?

[dr_mat 0]

Yes, I've always heard they closed the production line in May/June '95 too.. but you just don't know what's true and what's not do ya..