Hello everyone.

I think I may have finally figured out what's wrong with my 1800 dual carb camper.

It has been suggested to me by people, but a lot of other things have been too.

The van rattles and carries on when it's cold and the exhaust is uneven.
When it warms up the rattle disappears when idling, but the exhaust is still uneven. Initially I thought it was because it wasn't getting enough fuel or something. But I think I was looking at it backwards.
I thought that it was missing normally and occasionally firing on all cylinders. But now I think it's firing on all four normally and the extra chuffs in the exhaust are from a lifter jamming on an exhaust valve.
It also explains the awful clunks.

It's a pushrod motor and not a hydraulic one.

How do I fix this? please don't tell me it involves splitting the case!
If it does, you'll probably see a post in another section about putting a different type of motor in. I hate my van's motor so much. I've never seen a VW motor so unreliable.

[ Edited on 17-12-2005 by General_Failure ]

It won't be a lifter jaming, that just doesn't happen,
be more likely a loose valve seat or a burnt valve, do a compression test.

put a SUBARU EJ22 in it

The valve seats and valves are okay. Not amazing, but passable. It's done the exact same thing with two different heads. same sound, same problem, same place.

There doesn't seem to be anything majorly wrong with the carbs either.

All my pushrods are fine. The motor turns without any binding too.
All the rockers move as they should and are correctly adjusted.

The lifters were all I could think of.
When I get a chance I'll do another compression test.

Would it be safe to do a compression test with the motor actually running for a few seconds?
The problem doesn't seem to exhibit itself at cranking speed.

I* was going to put a subie motor in when the motor died first time. Found one on ebay. was outbid by someone called kombi_kim. different one though apparently.

yo tristan...

good to see your keepin form and still havin problems mate hehe

i cant suggest too much, never had one apart myself however a suggestion..

buy some 'lifter free', basically a cleansing agent you add to your oil and you rev for a while or so, and then drop the oil..

it cleans out your sludge and shit and so on, so it may solve the issue possibly? its shit cheap like $10 and just some new oil and a bit of time.... just an idea mate.. a cheap one for ya!

also with the compression test, its sposed to be done when at operating temperature. the closer you can get to replicate operating conditions, obviously the better (ie temp, revs etc..) in terms of accuracy of the reading....

good luck!!

Remove your pushrod tubes and pull the lifters out with your fingers(slide little finger in and try to get it out or use a magnet). Check the wear on the facing (rubs on cam). If you cant get them out they are stuck,most likely flattened on the facing. Cam will need to be replaced as well as the lifters refaced/exchanged.If that is the case the lifter bores might be scoured and more work to fix....there is an EJ22 and harness/ecu for sale cheap on here at the moment which will get you most of the way through a conversion.:tree

More likely the cam shaft and lifters worn out and giveing you and iregular seat so the valve clearences always vary. Pull the engine and strip it

Do you have any metal particles in the oil run a magnet in it next time you change the oil

So much information! No metal particles in the oil. It's perfect still.

The problem developed in a matter of minutes, so I doubt it's normal wear related. possibly horrible, catastrophic instant wear though.

Argh. I don't wanna take the motor out again The car's had 2 rebuilds in the last 100kms.

The last real drive it went on was to drop of the car trailer it was brought here on.
The vehicle towing it broke about 5km away from home.

Hah, wish I could go for the subie setup. Xmas is a harsh mistress though.

I'll check out the lifters next chance I get. Not sure when that'll be though.

Just took it for a testrun for the first time since I moved here (the towng its own trailer incident).
Fixed a few problems since, like leaky vacuum hoses etc. I was hoping I had made a difference. ot really.
It still idles kind of okay, but goes like a cow. It's 60km/h speed limited for some reason.

Anyway, getting to the point. Haven't done the lifter check yet. got too hot today. But I did a compression check on the afflicted (ie noisy) side of the motor. Both 3 and 4 gave me a respectable 115 PSI.

There was one oddity though. I think it was #3 cyl. The sparkplug was black. It looked oily but it was bone dry. Except for the thread. That was oily. The insulator, nut bit etc were all clean and dry too though.

The van blows no smoke whatsoever, so the weird gunky plug was a surprise. Could it still be a valve related issue? I don't know what to think anymore.

Im starting to think dodgey ignition leads here. Or at least the one on #3 neway.

Im not convinced its anything more sinister than that.
Try replacing them, hell just use a couple of lengths of plain wire if you dont have another set handy.

Make sire you carefully check the dizzy cap for cracks as well.
L8tr
E

Sounds like it could just be be not firing on one cylinder. Plug leads in the right positons?! Failed spark plug connector?.. Can check with multimeter, or visually for spark.
If valve/s were losing clearance it would stop it idling properly, or at all, but probably wouldn't feel so bad at 60k/h.

I was thinking sparky leads yesterday. Like I said though, it got too hot. It was only a back of the mind thing, because when I ran it quickly for the compression check, one of the plugs being unplugged didn't affect it noticably.

Well, it idles properly sometimes. Other days it's a bit of a pig, but the petrol's old so I forgive it.
With the idle screw set at factory position it idles at about 800rpm give or take. It's the take that doesn't feel right. When idling the motor is at 800rpm +/- 100rpm. It bogs down for about 2-5 seconds.

Spark order is absolutely correct. I've rechecked it more times that I care to remember. (Shows how much I trust myself).

I don't have any spare leads around, but I do have plenty of heavy gauge wire to do a quick check with.
According to my high voltage flashing screwdriver-whatsit there's a charge in the lead, but I don't know if it means it's getting through or not.

Oh, I tried swapping the suspect sparky in case it was at fault. It wasn't.

distributor cap is fine. No tracking or cracks. Rotor is okay too. I've even swapped it with a spare to see if there's any difference. I've also swapped distributors to check. No difference apart from crummier running because my spare is worn out.

I'll check with the wire later sometime. Just have to find the time. The sound of the van traumatises my daughter for some reason so it's pretty difficult.

Thanks for your help everyone!

Update! I tested the sparky cable. it was stuffed. So I shoved in a nice big wire to test. It was a little better. Running smoother. It still makes the nasty random clunky noise though.

I'm not sure if I'm right with this, but it _seems_ as though the clunk dies down after I block the idle throat for a few seconds (until the engine starts to suffocate). The engine runs at maybe 2000 rpm for 5-10 seconds after I do this really smoothy, then the revs drop back down to about 3-400 RPM. Then it struggles back to idle speed.

I'm pretty sure the noise isn't from a mechanical problem with the head. It did it with 2 different heads on. The head shims and barrel base shims were all replaced too. The rings and pistons are all fine too.