#2 compression = 60

[Markus]

Hi guys and gals,

My bus has been running rough for a while now. have done several compression tests over the last 6 months and #2 has gone from 90 to 75 to 60 and is now running very poorly. The motor is shaking/ surging/ sometimes stalls but ok at higher rpm. I pull the plug wire off #2 and nothing changes. I pull wire off of #4 and engine stalls. The other 3 comps are 125-140. This is not the original engine. I have a reciept from the late 90's that says "new 2.0 long block installed" and thats about it. Does does that mean the heads are original?


I see mike is buying a new engine. What do you suggest in my case? send heads out, bring entire engine to a shop? get new engine?

i know it could be rings but i have a feeling its the head.

any advice appreciate. 2L FI.

[Raj]

HI...
My gut tells me a worn cyl, bad rings. Do you have excessive blow by? Im not fluent in t4, but if the end play is good and was ' recently rebuilt' I wonder if this is a nice winter project. Yank the heads and check them out.... maybe a valve job. Check out the P&Cs..... should be good to go.

[Glenn]

Adjust the valves and check again. you might have a tight valve.

[Markus]

Oh yeah forgot to mention, checked the valves twice after the compression tests. One time it was a bit loose.

[Markus]

HI...
My gut tells me a worn cyl, bad rings. Do you have excessive blow by? Im not fluent in t4, but if the end play is good and was ' recently rebuilt' I wonder if this is a nice winter project. Yank the heads and check them out.... maybe a valve job. Check out the P&Cs..... should be good to go.

The crankcase breather is a bit wet but no blowby out of the oil filler or anything like that. I figured if its a cylinder i would see some blue smoke out of the pipe but it barely smokes at all.

The engine wasnt rebuilt, the longblock was replaced in 99 and the work reciept says nothing of the heads.

[Raj]

The engine wasnt rebuilt, the longblock was replaced in 99 and the work receipt says nothing of the heads.

'NEW 2.0L INSTALLED' threw me for a curve. I read 'new' and new or rebuilt...... sounds like you are suggest ' new' means... new to the bus.

Id yank the heads and look for the issues I suggested. Maybe another option is find another local t4 core ( read as mike) and rebuilt it. Milk what you have for now, then swap over the ' top end' and call it a day.

[Markus]

Right, heads have to come off regardless so I'll learn more at that point.

Theres no milking it anymore. I drove it saturday and its down on power, prone to stalling and the engine is physically shaking alot. Its officially down for the count. We'll see how much I can get done over the winter.

[Raj]

sorry man. At least it not during spring/summer/fall. And if your like me, Santa is super good to me and VW's! Make that list and fwd the hyperlinks to those that might need to know!

[SUMTHING]

pull the head off the #2 CYL side and check the valve guides, sometimes these brake and cause the valve sticking issue..

[Tom]

Also longblock includes heads.

[Markus]

ah ok, wasnt sure about that.

[ObnoxiousBlue]

Having the same issues here Markus. I haven't locked down which of the two "more popular" type IV buikders I'll have do my engine, and don't plan to lock anything down until late January.
I'm doing a longblock too, all to stock specs. Not doing anything over the top here, but will make a few common-sense upgrades while it is out - like the FI harness and a few other items that wear over decades.
More in my thread...

[Markus]

Yup I read your recent posts.

Spoke to the guys at Freccia Bros. They do top end work in house, send out the heads for valve seat jobs (3 angle) and guides.

Anyone have experience with them? They have been around for a while in greenwich, ct.

[Markus]

Update:

engine came out yesterday. Going to start taking off intake manifold, fuel injection stuff, tins, etc...

[Markus]

Finally got the #2 head, jug and piston off. The head looks ok on visual inspection aside from quite a bit of carbon build up, more so than #1. Cyls feels smooth and still some cross hatching visible at the bottom.

The #2 piston top most compression ring is stuck in the ring groove. I mean really stuck. about 180 degrees from the ring gap. And at that location the ring is flush with the piston outer wall.

Could this be causeing the 50% drop in compression?

Obv will need new rings. Is the piston damaged?

Now that i have 1 head off should i just go ahead and get the heads freshened up? WWGD?

[Glenn]

Finally got the #2 head, jug and piston off. The head looks ok on visual inspection aside from quite a bit of carbon build up, more so than #1. Cyls feels smooth and still some cross hatching visible at the bottom.

The #2 piston top most compression ring is stuck in the ring groove. I mean really stuck. about 180 degrees from the ring gap. And at that location the ring is flush with the piston outer wall.

Could this be causeing the 50% drop in compression?

Obv will need new rings. Is the piston damaged?

Now that i have 1 head off should i just go ahead and get the heads freshened up? WWGD?

I stuck ring can sure cause low compression.

Depending on your budget and your plans for the engine, I would go ahead and get the heads inspected and rebuild and install 4 new p/c.

[Markus]

Thanks Glenn!

wait does p/c mean pistons and cylinders?

yeah that could get costly.

[Glenn]

Yes... might was well do all 4.

Its cheaper to do it right the first time, than to fix it again later.

[Tom]

Thanks Glenn!

wait does p/c mean pistons and cylinders?

yeah that could get costly.

$414.85 to be exact.

http://www.busdepot.com/029198075

[Raj]

Nice work. Good to hear some time invested will point you in the right direction to fix her up!

[Markus]

yeah $414 isnt bad actually, huh.

[Markus]

Update: Brought the Top ends to Freccia Brothers in CT. (Realized I have 76-78 oval port 2L heads.). 2 pistons had dome damage from previous dropped valves that must have been fixed w/out replacing the pistons.

Recommendation was to just get the Mahle p/c set that glenn posted in the link and get new heads at $220 a pop from Bus depot. Theres a $95 core deposit. The guys at the shop said these are solid heads, 3 angle grinds on the seats, warranty and much cheaper than if they fully rebuilt mine. My heads have at least 1 siezed header stud, 1 spark plug helicoil, will need guides, etc.

I have a gasket set already and some new push rod tube seals so the whole damage will be about $900 for a full top end job. Not too bad.

Heads are ordered but have to be built, should be rolling by spring...

[Raj]

Nice! Post up pics as you rebuild. Im always intrigued by non t1 acvw engines as I have no experience on them.

[Markus]

Posting pics here has been my nemesis since I dont have photobucket but I'll try.

I've read that the BD heads are rebuilt by a shop in CA with questionable reputation. They are better than GEX but not close to adrian's heads.

I will do a solvent test on the heads to see if they leak. I have lapping compound and have done that before if need be.

[Tom]

Nice! Post up pics as you rebuild. Im always intrigued by non t1 acvw engines as I have no experience on them.

The only real difference is the location of the fan and oil cooler and that the fan is driven by the crank and not a belt.