VR6 Compression Ratings - Dry/Wet

[petemcr 2]

Afternoon fella's

 

Hope you're all doing well on this wet and windy Monday.

 

Just wanted some opinions on this, I've done the head gasket on my VR6 some time ago, not really touched it much but I've started working on her again, just in the process of removing the head but, I did a compression test on all cylinders and they were rather disappointing, I've suspected the head hasn't been correctly installed so I suspect head issue as she was running fine prior, just minor oil burn when she was in the high revs but fine down low.

 

So, dry compression test showed the following.

 

Cylinder #1 - 30 PSI

Cylinder #2 - 60

Cylinder #3 - 40

Cylinder #4 - 50

Cylinder #5 - 50

Cylinder #6 - 40

 

After the poor results, I did a wet compression test on two of the cylinders again to check there wasn't a dramatic increase.

 

Cylinder #1 - stayed at 30 PSI

Cylinder #3 - Went up to 70

Cylinder # 4 stayed the same.

 

From my understanding, this would indicate a head issue, burnt valve/bent/poorly seated head.

 

While I have the head off, does anyone know any good means to test the pistons don't have too much slack in them, going to do the head gasket again, but it would be nice while it's off to be able to test them.

 

Any help would be amazing to help get the old girl back on the road.

[VR6Pete 1,455]

If goes up on wet test, then I would say more than likely worn rings. 

 

What mileage is the engine on?

[VR6Pete 1,455]

For reference a good reading is 170 psi on a freshly built engine so seems to be very low across the board with your engine

[petemcr 2]

Alright buddy, yea I think the head has been put on badly, I compression tested the rest of the pistons and they were all down so
I've taken the head off today and the head bolts were, well they weren't tight at all. Cheers for the info on what PSI they should be fella, I'm going to do the gasket and head again and torque them correctly then see what I get

[petemcr 2]

just to open this up a little more.

 

Heads off, found some scoring on one or two of the cylinders, I still think the gasket wasn't sealing which was the low compression but hoping for a bit of advise.

 

I did plan to just put the new head gasket on and get the head pressure tested just to get her back on the road, kind of torn now with what to do, I don't know if to try and get another block, 2.8 (I've heard they have less issues due to the thicker cylinder walls) but I didn't want to go down this route so soon.

 

How badly is the engine going to run if I was to put it back together for the time being till I can get bottom end work doing? am I going to have a bad time if I put her back together as is just to get her back on the road?

[MJ Vr6 79]

Your better of sending the block away to see what can be done down below.

May need to invest in some new bigger pistons.. 

Would you wanna buy a 2nd hand block and go down the same road, or would you rathe fix what you have? 

Think about it.... 

If you are in London I can put you in touch with some specialists friends of mine who re-bore blocks and sort Cylinder heads daily, just finished my mates R32T and my R32. 

 

Mj

[petemcr 2]

1 minute ago, MJ Vr6 said:

Your better of sending the block away to see what can be done down below.

May need to invest in some new bigger pistons.. 

Would you wanna buy a 2nd hand block and go down the same road, or would you rathe fix what you have? 

Think about it.... 

If you are in London I can put you in touch with some specialists friends of mine who re-bore blocks and sort Cylinder heads daily, just finished my mates R32T and my R32. 

 

Mj

 

 

You are right, plus it would be nice to have the correct serial number matching with the car, my plan was to get a 2.8 VR6 and have it bored out to 2.9 and then use my pistons.

 

The bottom is still in the car at this stage, I was just planning on doing the head gasket really but this has changed my plans, I'm in Manchester fella but appreciate the help.

 

I will have to see about getting the bottom end out now I reckon and go from there.

 

Thanks guys

[MJ Vr6 79]

OR........ 

Find a Raddo Bottom End. 2.9

Go and see one thats stripped so you can actually see what the Bores are physically like.. At least in that way can cut costs down, work on your head.. Theres ways mate.. ???

[petemcr 2]

You know, there is one on eBay at the moment which I have been looking at, I was avoiding the 2.9 bottom end because I thought it would be a waste, but it would be nice to have another block set aside to work on that can just be swapped out eventually.

 

Cheers for the advice fella, going to see what I can find.

[MJ Vr6 79]

No worries mate!! ??

[petemcr 2]

This is the block I've been looking at, it's the bare bottom end, but I've just messaged the fella asking for details asking about the millage of this, he has told me it had done 315K when it was removed, no smoke or rattles 

 

Now, I know the VR6 was a tough engine, but my god, is this going to be a dead stick to work with and I mean no disrespect if the person is on here. He did point out and I can see it in one of the pictures that it still has the cross hatching on the bores, I've looked at mine which had done 184k and even that doesn't have the cross hatching.

 

http://www.ebay.co.uk/itm/282461797771?euid=79d0c8618e6e4fb180f9715ef961776b&bu=43789417512&cp=1&sojTags=bu=bu

Edited June 1, 2017 by petemcr

[MJ Vr6 79]

No pistons..... Lipped bore. 

Pass. 

But its up to you. 

[petemcr 2]

Yea that's what I figured, just wanted an opinion.

 

I might hold out till I can find something in better condition, or just bite the bullet and pull my bottom end out and work with that, better the devil you know and all that.

 

Cheers again

[MJ Vr6 79]

Mate, on Ebay type in item number 222130362136. 

 

Give them a call or Inbox them.. 

Good luck. 

 

Mj