rusty cylinder walls rebuild question
 

ok, i have 2 rusted cylinder walls on a 6 cyclinder motor. its a little more than just surface rust. i know the best way to go about this is to bore it out and spend alot of $$. i just need this thing running and i dont care about premature wear. i am wondering if i would be able to get away with honing the walls and putting on some new rings.. if i get done honing and it has some pitting on the walls should it run ok? any help from someone who knows about this from exp is appreciated.. i have pics

Re: rusty cylinder walls rebuild question
 

Another motor salvaged from the titanic wreckages....that's two this week. Lol.
judging from the pictures, that thing is dunzo without a bore and decking. What do the main/rod bores look like? What motor is this? It might be cheaper to pull one from the yards. This one looks like one from the yards that had the head removed and sat there with no hood for a good decade.

Re: rusty cylinder walls rebuild question
 

this is a vw vr6 motor that was sitting for maybe 2 months with bad head gasket. had water sitting inn the cylinders when i pulled the head, i haven't looked at the bearings yet. i just dunno what to do with this,, i would have to get new pistons if i bored it out right? a hone wouldnt take alot of that out? shiat sucks

Re: rusty cylinder walls rebuild question
 

Needs to be heavvvvvvily bored judging by the condition of the tops of the cylinders. This is the most important area....the head/block gasket mating territory. Im not familiar with the oem bore size, nor available aftermarket bore sizes for this motor. Im a honda guy. This is also only judging from the limited quality of the pictures you provided. This is what im judging it off of. Provide better close up pictures of the cylinder walls as well as the very tops of each. Cylinder and ill be able to give you a better, more definitive answer.

-jay

Re: rusty cylinder walls rebuild question
 

hey thanks for the input, i will try to get better pics so i can maybe get a second opinion.

Re: rusty cylinder walls rebuild question
 

This will need to be bored for sure. The question is how much? Well you're going to need to measure each cylinder with a dial bore gauge and find the worst worn cylinder. (Stock bore size for a 2.8 liter VR6 engine is 81mm) To determine how much you need to bore will depend on how bad the worst cylinder rusted/worn, for that cylinder you will need to double the taper wear. For example if there is .015" taper on the worst cylinder then a general rule of them is it will need to be bored .030" oversize. When boring the block you will need to leave anywhere from .003" to .005" left to remove that will be honed out to achieve to proper cross hatch pattern need on the cylinder walls.

VR6 motors can be very complicated because although the cylinder look straight up and down, they are not. It is a 15 degree V shape. A standard boring bar cannot cannot bore this block because the cylinders are not straight up and down. However if not much is needed to get the rust and wear cleaned up it is possible the imperfections can be honed out which can be done on a standard honing machine. Most likely this is not the case judging by the pictures.

As a caution to you, oversize piston are god awful expensive for vr6 engines...find a used block if you can. It will save you money and time.

Also looks like the deck surface is going to have to be milled down a couple thousandths if the 40grit sand paper a block of wood does not fix it.

Try this forum for more information:
http://forums.vwvortex.com/forumdisp...6-Engine-Forum

Built one of these before and it was not that much fun....haha

Re: rusty cylinder walls rebuild question
 

hey, i wanted to revive this thread to let everyone who is interested know that instead of taking the block to a machine shop to have it bored out and what not, i decided to clean it up as best as i could with sand paper and try my luck. well after putting everything back together i expected the car to burn oil like hell but to my surprise it runs just like it did before the blown head gasket. im not posting this to prove anyone wrong, this info is for anyone having a similar problem and cant afford to fix. not saying it will work for everyone but it did for me! cheers :beer:

Re: rusty cylinder walls rebuild question
 

So is the VR6 engine laid out cylinder wise like the W12? I have never paid much attention to the VW motors.

Re: rusty cylinder walls rebuild question
 

i couldnt tell ya, this is my first time workin on a vw. all i can say is the block is about as big as a four cylinder and it has 20 head bolts so i got a little work out torquing those suckers. cool design though

Re: rusty cylinder walls rebuild question
 

Kinda, think of the VW W12 as making a new Vee out of 2 VR6 engines. Similar to a V8 making a new Vee out of 2 inline 4 honda motors.

Re: rusty cylinder walls rebuild question
 

Yeah thats what I was thinking, I always thought it was a v6. I have never been a Vdub fan, other than the old beetle flat 4 engines.