Mark Anderson

So we shipped a used engine and the customer is saying that there is 0 compression in cylinder #2. They did replace the belt and water pump before installation. We do compression tests on all motors before shipping so it was good when we shipped it. My one thought was did the mechanic take the belt off at TDC instead of 45 and would the cams moved enough to tag some valves. We asked them to spray WD40 in the hole and check again and still 0. All other cylinders have reasonable compression.

The motor is S4
Any other ideas or possibilities?

BTW the car is in Yorktown Heights NY

James Bailey

What else did they do ?? intake removal /refresh ?

Mongo

Valves. Someone missed the memo about the 45 degree mark.

Mark Anderson

they did take the intake manifold off

Mark Anderson

that was a guess of mine but I don't know if that would do it. I was hoping someone might chime in that it happened to them and yes it was #2 that bent valves

Imo000

Have them put a scope down the #2 and see if all looks normal. There could be something stuck between the valve and the seat.

Mark Anderson

do any bore scopes look back?
we first thought maybe some carbon under the valve but after running it a bit I would have thought it would clear up

Mongo

Ah, Imo has a good point. If you're removing the intake, there is bound to drop some remnants of an old gasket into the intake ports. One of the first things I did when I did my intake back in 2009 was take a vacuum cleaner to all intake ports where the valve was closed after having a peak down it. Anything else that dropped past the valve and into the chamber I prayed would not fowl up the exhaust..... and yes there was lots of Permatex orange used by the previous owner's mechanic, Julio.

Dave928S

My first thought was also something dropping down an intake and getting between a valve and seat. If there had been a timing/valve event you'd think it would be more than one valve.

I have a German made optical borescope that has a very wide field of view, has a super bright halogen light, looks at 90 degrees to the 8mm shaft, and can see all the chamber and valves ... but I'm a bit far away to lend it to anyone in the US

I do have a couple of cheaper video borescopes which have small mirror attachments which allow you to look back to a reasonable degree, and I'm sure they would also do the job, but the clarity isn't as good.

Hopefully it's only a bit of gasket and not metal.

Herman K

0-180 degrees

http://www.ebay.com/itm/301915679388?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Dave928S

^^^ Wow, that's neat! I think I'll order one.

hlee96

You mean like this?

granprixweiss928

I have the cheap harbor Freight scope and it comes with a little clip on 45deg mirror for the end sp u can see the sides, which means valves too as soon as its thru the plug hole. Remove the mirror and it looks straight down at the piston top

dr bob

Mark-

Easiest way to find the cylinder leak is by putting the suspect cylinder at TDC and putting a little compressed air in through the plug hole. They will be able to hear any air escaping. Doesn't take a lot of air volume, and depending on the fitting used on the plug hole less can be better. I have an old "bargain" compression gauge that uses a short hose with a air-line disconnect for the gauge. A mating disconnect on a regulator lets me put as much or as little air in there as needed. Point is though that it's an easy way to connect air to the cylinder for any pressure or leak testing.

Mark Anderson

The mechanic seems to have limited abilities but I will ask.