TheSamba.com :: View topic - Metal in valve cover-pics

Mon Sep 29, 2014 9:17 am

Sequence of events: went camping last weekend in the hills of TN. I noticed a loss of power in the return trip. When I got home I changed the oil and adjusted the valves. No change. I looked at my plugs and #1 appeared wet. I checked my wires and # was corroded. I changed plugs and wires and my power was back but I developed a bad tick after 5 minutes of driving. Today I removed the valve cover to check my specs and these metal bits were in there and #1 was a little loose. I put it back and went to get gas (probably dumb) and it blue smoked due to a pretty bad oil leak. See the photos. Any idea what those pieces are? My push rid tubes are metal and appear intact.

Mon Sep 29, 2014 9:32 am

Quote: and it blue smoked

parts look like, and symptoms above point to a broken valve guide. Do not run the engine until the heads are rebuilt or replaced lest the valve cock and hit the piston. You may have dropped a valve seat which cocked the valve enough to break the guide. I see Adrian at Headflow Masters in your future for rebuilt heads, or Len Hoffman at HAM if you want new ones.

Mon Sep 29, 2014 9:58 am

SGKent wrote: Quote: and it blue smoked

parts look like, and symptoms above point to a broken valve guide. Do not run the engine until the heads are rebuilt or replaced lest the valve cock and hit the piston. You may have dropped a valve seat which cocked the valve enough to break the guide. I see Adrian at Headflow Masters in your future for rebuilt heads, or Len Hoffman at HAM if you want new ones.

X2...and also why is that outer valve adjuster cranked out so far? I would investigate that also if you do not know. Ray

Mon Sep 29, 2014 10:07 am

SGKent wrote: Quote: and it blue smoked

parts look like, and symptoms above point to a broken valve guide. Do not run the engine until the heads are rebuilt or replaced lest the valve cock and hit the piston. You may have dropped a valve seat which cocked the valve enough to break the guide. I see Adrian at Headflow Masters in your future for rebuilt heads, or Len Hoffman at HAM if you want new ones.

So it's roasted? Here's another pic of the metal bits. What would cause this? What's a rebuild run these days?

Thanks!

Mon Sep 29, 2014 10:18 am

Quote: What would cause this?

Lots of ways if one thinks about it for a second.

dropped or loose seat that lets valve cock
crack running into guide that causes it to come loose
poorly fitted when rebuilt last time
cracked on installation or in manufacturing and it finally failed
fatigue although it is rare but not unheard of to see them fail this way
valve head snapped off
valve seat is sinking into head and the valve hits the guide
etc, etc

Quote: What's a rebuild run these days?

http://www.headflowmasters.com/vw-engine-head-machine-work.html#.VCmUrxYXMmg best to call Adrian and there may be other damage to the head. I believe price is each valve so multiply X 8.

New heads: http://www.hamincgroup.com/vw.php

Mon Sep 29, 2014 12:16 pm

That guide must have been loose and worked its way up the bore, at least that is how I see it. Our present fuel rots in a few months and then will cause the valves to stick in the guides, so maybe this was a contributing factor. Yes it does look like you have severe valve train recession on that one exhaust valve and maybe some recession on other valves as well.

Head work isn't cheap, but it is the real heart of these engines so it is worth paying mucho dollars for.

Thu Jan 08, 2015 1:39 pm

Okay..... so I did this

Found this...

and this..

My questions is. Do I get the heads rebuilt and slap them back on and run it? Is the scoring in that cylinder going to mess me up? I'm trying to stay as economical as possible while not jeopardizing the life of the motor. Thoughts?

Thu Jan 08, 2015 2:38 pm

That engine's using alot of oil and the scoring from the carbon buildup isn't helping, you could slap it back together and get a few more years out of it as is but since it's out and apart there's no time like the present for some new pistons and cylinders. How's the cam look?

Thu Jan 08, 2015 4:06 pm

I would replace the cylinders and pistons with a new set if you can afford it. That means you'll probably split the case and rebuilt it with new bearings too. So if there isn't money for that, just pull the cylinders off after clearly marking them, have the pistons cleaned at the machine shop, buy some new rings and have the machine shop bottle brush the cylinders.

Thu Jan 08, 2015 4:30 pm

Beware that if you split the case there have been some unusable sets of main bearings out there. Best to buy from a know reliable source. If your cam is half way decent and you had good oil pressure, it might be a good idea to think twice before splitting the case.

Thu Jan 08, 2015 7:39 pm

That cylinder didnt suddenly go to hell and start blowing oil, and thats not where its smoking from most lekely. That pic of the head, there is what appears to be a bare metal spot, a divot, on the outside of the left combustion chamber. The broken bits look like bronze and do appear to be the remains of a valve guide. As the guide "guides" the valve, and as its probably broken, the valve head is wobbling all over and likely left that mark/divot. Bet you pop the spring and valve out youll see your problem. Broken guide, wobbling valve, it sucks air and oil and blows a lot of smoke.

From there is a crap shoot. Only you know how it ran, what it had for oil pressure, etc.. You could get a pair of decent heads and put it back together and it will run the same as before or better than ever. Or dig deeper. It is a simple engine...

I helped pull a jug off a Cessna 152. The motor was a fresh overhaul in for an annual that had one cylinder with low leakdown from a leaking exhaust valve. We just redone that one jug. Honed the cylinder, redone the head, slapped it back together and watched it fly away. Well, after running it up and checking it out first.

Thu Jan 08, 2015 7:54 pm

Artvonne wrote: That cylinder didnt suddenly go to hell and start blowing oil, and thats not where its smoking from most lekely. That pic of the head, there is what appears to be a bare metal spot, a divot, on the outside of the left combustion chamber. The broken bits look like bronze and do appear to be the remains of a valve guide. As the guide "guides" the valve, and as its probably broken, the valve head is wobbling all over and likely left that mark/divot. Bet you pop the spring and valve out youll see your problem. Broken guide, wobbling valve, it sucks air and oil and blows a lot of smoke.

From there is a crap shoot. Only you know how it ran, what it had for oil pressure, etc.. You could get a pair of decent heads and put it back together and it will run the same as before or better than ever. Or dig deeper. It is a simple engine...

I helped pull a jug off a Cessna 152. The motor was a fresh overhaul in for an annual that had one cylinder with low leakdown from a leaking exhaust valve. We just redone that one jug. Honed the cylinder, redone the head, slapped it back together and watched it fly away. Well, after running it up and checking it out first.

I sincerely hope that was not one that killed my roommate a few years ago when a spark plug coughed out of a cylinder.

Thu Jan 08, 2015 8:12 pm

Sorry you dont know how aircraft engines are repaired.

Fri Jan 09, 2015 6:17 am

Artvonne wrote: That cylinder didnt suddenly go to hell and start blowing oil, and thats not where its smoking from most lekely. That pic of the head, there is what appears to be a bare metal spot, a divot, on the outside of the left combustion chamber. The broken bits look like bronze and do appear to be the remains of a valve guide. As the guide "guides" the valve, and as its probably broken, the valve head is wobbling all over and likely left that mark/divot. Bet you pop the spring and valve out youll see your problem. Broken guide, wobbling valve, it sucks air and oil and blows a lot of smoke.

From there is a crap shoot. Only you know how it ran, what it had for oil pressure, etc.. You could get a pair of decent heads and put it back together and it will run the same as before or better than ever. Or dig deeper. It is a simple engine...

I helped pull a jug off a Cessna 152. The motor was a fresh overhaul in for an annual that had one cylinder with low leakdown from a leaking exhaust valve. We just redone that one jug. Honed the cylinder, redone the head, slapped it back together and watched it fly away. Well, after running it up and checking it out first.

You are correct. That valve guide is toast and that was the damage from the valve. To be honest, it was running great until all this happened. 6 months ago we made a 10hr road trip to Florida with all our camping gear, no problem. I think I'll get the heads rebuild, slap them on and see where it takes me. I'm saving up for a proper 2.0l, but can't afford it now. CHT gauge will be going in because I feel that this could have been avoided if I had that.

Thanks for everyone's feedback! I'll update this post when it all goes to hell :shock:

Fri Jan 09, 2015 6:37 am

Don't assume that looking at the inside of your heads and seeing the valves is going to give you confidence:

http://www.thesamba.com/vw/forum/viewtopic.php?p=7497339&highlight=#7497339

Fri Jan 09, 2015 10:37 am

Wasted youth wrote: Don't assume that looking at the inside of your heads and seeing the valves is going to give you confidence:

http://www.thesamba.com/vw/forum/viewtopic.php?p=7497339&highlight=#7497339

I'm not assuming. The head has been to a very reputable air cooled specialist. He's confirmed everything for me because I am a newb.

Fri Jan 09, 2015 12:13 pm

CurbRogerD wrote: Wasted youth wrote: Don't assume that looking at the inside of your heads and seeing the valves is going to give you confidence:

http://www.thesamba.com/vw/forum/viewtopic.php?p=7497339&highlight=#7497339

I'm not assuming. The head has been to a very reputable air cooled specialist. He's confirmed everything for me because I am a newb.

There are only 2 that many trust these days when it comes to Type-4 heads...

Adrian - Headflow Masters

Len Hoffman - Hoffman Automotive Machine Inc.

I'd be VERY weary of anyone else.

Fri Jan 09, 2015 12:47 pm

Artvonne wrote: Sorry you dont know how aircraft engines are repaired.

or not repaired in the case of losing my housemate. The FAA said a spark plug puked climbing out after an engine rebuild and then ensuing chain of events led to a crash before the aircraft could get back and land. I also have another friend who had a crankshaft snap in half on his way back from Catalina to Hawthorne shortly after a factory rebuild but fortunately he had enough altitude to declare an emergency and make one of the many airports near LA deadstick. The crank had a casting flaw that had not been detected in inspection during the teardown. These type events are exceptionally rare but you can't go into denial and say they don't happen.

Fri Jan 09, 2015 1:26 pm

SGKent wrote: ... These type events are exceptionally rare but you can't go into denial and say they don't happen.

My experiences:

C-124 14 engine failures in 2800 hours
complete electrical failure between Hawaii and the mainland
oil dumps and generator failures

T-38 compressor stall on takeoff roll

B737 compressor stall on takeoff roll
indication of loss of oil pressure on climb out
bird strikes and compressor damage
freaky passengers
aircraft hit by a stolen car
swarm of bees on takeoff roll causing loss of engine instruments

single engine aircraft and VW's are a crapshoot, but 99.99% safe if well maintained

New or recently overhauled engines and very old engines were usually the most troublesome. Like VW's, an engine with some time on it is the most reliable.

Over to you Gary

Aloha
tp

Fri Jan 09, 2015 4:28 pm

Tom Powell wrote:
New or recently overhauled engines and very old engines were usually the most troublesome. Like VW's, an engine with some time on it is the most reliable.

I have kids now. I don't fly piston engines past TBO (well maybe if I owned the engine since rebuild and nobody else flew it).

I've done a few piston motor break-ins....circling above a looooong runway for a couple hours. After that I'll let somebody else put the first 50 hours on it (unless it's a twin).

Turbines OTH are pretty reliable...if it spools up OK, it's good to go even after a rebuild. Failures are exceedingly rare unless it involves an outside object getting inhaled by the fan.