Roid shut itself down

[fabricator]

Welp, last night I noticed something was missing from the normal back ground noise, the minute I stepped into the shop I realized the roid was down, I checked the fuel, plenty, checked to see if it was seized, nope, no unusual noises when hand cranking but not the usual hard stop against the compression stroke, I can actually crank it over by hand on the compression stroke.
I'm thinkin stuck or broken rings, it's been running pretty much non stop since January and I know Lister had a decarbon schedule so I'm gonna pull the head and take a look.

[ottawavalleyboy]

That's not cool....I hope it's all straightfoward for repairs, I have to dig into mine to check for carbon too as it's brand new to me.The previous owner wasn't 100% sure there was a element int the fuel filter when he called to see how mine ran.

[BruceM]

Chunk of carbon holding a valve open is the most common cause of sudden loss of compression, but if so, you can hear the air leaking into the guilty valve (inlet or exhaust)  during compression. Rapping on the valve stem rocker a few times will usually dislodge it. 

Rings all going suddenly bad doesn't compute, to me.

[Thob]

How much oil is in the crank case?  I've seen engines that ran until they seized, and then once they cooled off they were free again would actually (sort of) run again.  It would probably be a good idea to pull off one of the covers and take a good look down there for any metal pieces as well.  Search around with a magnet, or remove and inspect any magnets you already have down there.

[potter]

I would lean to the carbon under a valve, I have had this happen to me Two times  burning wwo .

[fabricator]

Well it was a combination, the middle compression ring was stuck about half way around and the exhaust valve had carbon built up on the valve and the seat, after over 2000 hours it's still got a nice cross hatch and just a very slight ridge.

http://i2.photobucket.com/albums/y6/fabricator01/photobucket-46104-1334021898923.jpg

http://i2.photobucket.com/albums/y6/fabricator01/photobucket-50560-1334021775693.jpg

http://i2.photobucket.com/albums/y6/fabricator01/photobucket-46100-1334021729417.jpg

http://i2.photobucket.com/albums/y6/fabricator01/photobucket-24576-1334021696374.jpg

[BruceM]

I don't see anything that would account for the loss of compression- must have been a carbon chunk under a valve.
The cylinder looks fabulous, and you carbon situation is very minor for your engine hours. I think you have a real gem of an engine, and your prep and setup work was excellent. 

[selmawp]

Hi, as a new bee I would like to introduce my self I have werkt on VW's since 64 in mid 80's I started to werk on many diesels in 92 I moved from California to Oragon and for 5 years I have rebuilt well over 500 VW diesel heads that sed from what I can see on #2 pix

the seat is slightly out center but the biggest problem is that the valv is making full contact with the seat, I recomend while the head

is off that you have valv seats instald and do a 3 angel valv jobe the contact area of the 45 degree should be no more than 0.030 for that way you would

elimenate 90% of the carben build up also with installing seats you can open the ports witch will improve power  quete a bit, howe

do I know this? A friend of myn hase a 10/1 that is been running now for 7 years and the only thing we had to do last summer was

replace the head gaskit, we are in process of writing our expierience and soon this is finisht we will post it.  Tony the Dutchman.

[fabricator]

I don't see anything that would account for the loss of compression- must have been a carbon chunk under a valve.
The cylinder looks fabulous, and you carbon situation is very minor for your engine hours. I think you have a real gem of an engine, and your prep and setup work was excellent. 

In pic # 2 the bottom side has been scraped clean, the top side still has at least 1/32 of carbon on the seat, it's pretty hard to see it, and it was uneven definitely not seating fully, and the middle compression ring was stuck solid right in the area where the piston has the carbon build up, the other side is as clean as when it was new.

[overbore]

Hi, as a new bee I would like to introduce my self I have werkt on VW's since 64 in mid 80's I started to werk on many diesels in 92 I moved from California to Oragon and for 5 years I have rebuilt well over 500 VW diesel heads that sed from what I can see on #2 pix

the seat is slightly out center but the biggest problem is that the valv is making full contact with the seat, I recomend while the head

is off that you have valv seats instald and do a 3 angel valv jobe the contact area of the 45 degree should be no more than 0.030 for that way you would

elimenate 90% of the carben build up also with installing seats you can open the ports witch will improve power  quete a bit, howe

do I know this? A friend of myn hase a 10/1 that is been running now for 7 years and the only thing we had to do last summer was

replace the head gaskit, we are in process of writing our expierience and soon this is finisht we will post it.  Tony the Dutchman.


Tony, can you quote on doing a three angle valve job on a new 10/1?

Many thanks, overbore

[fuelfarmer]

fabricator, I know this is a stupid question. Were you running  B100 all the time?  Trying to get a small glimpse into the future.

[fabricator]

No, straight centrifuged wvo, and that includes the break in period with a LOT of experimentation, I pretty surprised it wasn't a lot worse.

[mikern]

My FieldMarshall did the same after about 18months straight running,( on WVO), ended up being a small carbon chunk under the ex valve. did a valve job at the same time, and no problems since. Mike

[fabricator]

Did you have seats installed and get a three angle job?

[overbore]

NAPA shops can do good valve jobs but do they work on our 'Roids for three angle jobs? 

overbore