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Fri May 23, 2008 5:57 pm

Hello All,

'86 Westy 2.1 litre stock, standard transmission

Any help would be appreciated, I'm hoping its not a dead cylinder:

Just bought the van, had it compression tested and got:

#1 90 PSI
#2 30 PSI
#3 135 PSI
#4 125 PSI

But the van ran perfectly fine, very strong. Took it on a long trip last weekend, about 300 kilometers in it started 'chugging' in all gears except not very noticeable in 1st. First thought, vanagon syndrome, stopped and started the engine, did not go away. Had pigtail from my old van, did not go away. 2nd idea, distributor cap, cables etc...all check out fine. 3rd idea, O2 sensor, unplugged it, still happened, plugged it back in.

Van now sometimes stalls when coming down from higher RPM, ie stop light. OR sometimes revs high, creeping its way up to 1800 RPM. No appreciable difference between hot and cold. Coolant light blinked a bit before it occurred, but I put more coolant in and all is fine on that end.

Does not 'chug' when cruising at speed, but does when accelerating. Have no real problems getting up to speed, still feels strong except for the chugging. Can still cruise at 100 - 110 kph....hills are slightly slower...gas mileage dropped but not significantly.

Any help on where to look would be appreciated.

Thanks,
Gregor

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Fri May 23, 2008 6:05 pm

Thats about the way my compression read in Mazatlan Mx. we ran for the states (no parts in Mexico) we got within 100 miles it got tougher and tougher to drive then finally one of the two working cylinders quit & would no longer start, we fell in love with the old girl for standing up so well. We put in a long block in Tucson and away we go. We live in the Okanagan BC so couldnt get into doing a rebuild ourselves. Lotsa luck but your motor needs rings and valves minimum.
Tony

Fri May 23, 2008 6:10 pm

Hey Dude,

A compression check is the "first step". Now you should have a leak-down test done to pinpoint the cause of the leak at cylinder no. 2. Depending upon where/what the leak is, that will determine the amount of work (and $) that needs to be performed.

Quoting from Wikipedia...

If there is a significant (> 10%) difference between cylinders, that may be an indication that valves or cylinder head gaskets are leaking, piston rings are worn or that the block is cracked. If a problem is suspected then a more comprehensive test using a leak-down tester can locate the leak.

What is engine compression.

http://en.wikipedia.org/wiki/Compression_ratio

Explanation of a leak-down test.

http://en.wikipedia.org/wiki/Leak-down_tester

Good luck,

Chester

Fri May 23, 2008 6:17 pm

I would guess you have more than one issue going on. First off, you ned to make sure you have no vacuum leaks or cracks in the intake boots. Then you need to check the infernal Throttle Switch for proper operation. Also, replace the Temp II Sensor. It controls the warmup mode.
http://www.van-cafe.com/vanagon_parts.jsp?pa=p&p=1258418664&pct=128189133&ct=5646608

Here is a quick run down on what to do:

Fri May 23, 2008 6:44 pm

check your timing. mine chugs under acceleration when the timing is off a bit. i would check those compression numbers again and with a different gauge if possible. engine would barely run with those numbers.

-rb

Sat May 24, 2008 7:34 am

rblake3 wrote: check your timing. mine chugs under acceleration when the timing is off a bit. i would check those compression numbers again and with a different gauge if possible. engine would barely run with those numbers.

-rb

Thats what I thought. That cylinder was checked 3 times, along with one of the good cylinders....they got the same numbers each time.

Gregor

Sat May 24, 2008 8:12 am

Thanks!

I see, after some searching, that this is your standard reply (throttle switch).

Thanks for your patience with us :-)

Gregor

Sat May 24, 2008 8:59 am

Did you get it running better? That #2 cylinder is cause for concern. Leak down test is required for sure. Probably should start saving money for new motor or heads.

The TPS is probably the no 1 fault for people who have never checked it. Once it is set however, you never need to mess with it again-usually. If everything else mentioned has been checked, the idle stabilizer control can cause issues, try disconnecting it and test run.

-rb

Sat May 24, 2008 10:05 pm

Before you do the leak-down and the 2nd compression test, first, get the timing fixed, of course, remove the spark plugs and use a funnel and some tubing to put 2-3 tablespoons of Marvel Mystery Oil in each cylinder.

Let that sit overnight, replace the plugs, start your van, and watch the artificial fog bank form! Drive it a bit, then come back and repeat the procedure.

You just MIGHT knock your rings loose again. That would help A LOT.

Best!

Sun May 25, 2008 7:57 am

gbrandt wrote: Hello All,

'86 Westy 2.1 litre stock, standard transmission

Any help would be appreciated, I'm hoping its not a dead cylinder:

Just bought the van, had it compression tested and got:

#1 90 PSI
#2 30 PSI
#3 135 PSI
#4 125 PSI

But the van ran perfectly fine, very strong. Took it on a long trip last weekend, about 300 kilometers in it started 'chugging' in all gears except not very noticeable in 1st. First thought, vanagon syndrome, stopped and started the engine, did not go away. Had pigtail from my old van, did not go away. 2nd idea, distributor cap, cables etc...all check out fine. 3rd idea, O2 sensor, unplugged it, still happened, plugged it back in.

Van now sometimes stalls when coming down from higher RPM, ie stop light. OR sometimes revs high, creeping its way up to 1800 RPM. No appreciable difference between hot and cold. Coolant light blinked a bit before it occurred, but I put more coolant in and all is fine on that end.

Does not 'chug' when cruising at speed, but does when accelerating. Have no real problems getting up to speed, still feels strong except for the chugging. Can still cruise at 100 - 110 kph....hills are slightly slower...gas mileage dropped but not significantly.

Any help on where to look would be appreciated.

Thanks,
Gregor

[/youtube]

On water cool vanagon the pistons a ralely the problem in regard to compression. Not like the Air-Cool, those had a 50 50 chance of having all kind of pistons related problem.... or head.

Valves/ valve seat " burned valve are also not a major problem on Water cool. Mostly you have a Head Gasket failure. Could be a crack also.

Water cool engine will also run nicely with low compression, it won't even show much on falt raod. But i agree, 30 is to low. I would not care much about 90psi. I see that very often.

Ben

Sat Jun 07, 2008 5:55 pm

Ok, life has been crazy and I just got around to looking at this issue.

Check the TPS...it was off, but not by much. Now works correctly (haven't done throttle cable tests yet, but everything i could by myself at the back of the van is done) Now reads 0.04 ohms at no throttle < 0.07mm and infinte ohms at 0.10 mm. Van still exhibits problems mentioned at the top if this thread.

I have a temp II sensor on order.

A few questions:

1. is 0.04 ohm close enough to 0.0 ohms for the switch to be ok
2. One of my injector boots looks like the picture attached. It looks like the clamp has moved a full clamp width+ away from where it should be, this may be causing a leak (Am I correct in that assumption?). How in the *** do I move a clamp like this? I'm tempted to just cut it off an replace with a screw type clamp. This is on cylinder 1 ( passenger side, front of vehicle)

bigger image here
http://personal.marionette.ca/intboot2.JPG

Any more help is appreciated. I am learning :-)

Thanks,
Gregor[/list]

Sun Jun 08, 2008 8:24 am

Never post on a saturday evening :D

sorry about this but today is the only day I can work in it until next month....

Bump

Gregor

Sun Jun 08, 2008 8:53 am

You've got big problems, and it isn't in the TPS or coolant temp sensor, or a vaccum leak.

What you have here is a dead hole, and a low hole, and scrounging around outside of the powerplant isn't going to create a miracle.

You've either have a burnt valves, or collapsed rings.

Remove the engine, take the upper end apart , and locate & correct the problem.

Ajusting the TPS isn't going to restore lost compression in them two holes.

Sun Jun 08, 2008 9:12 am

When you're using your ohmmeter, before any continuity check you always touch the probes together. This both confirms that you have a circuit thru both probes and tells you what the actual zero indication is on the meter. Digital meters rarely go fully to zero on ohms. Then you know the offset in that range and can compensate. 0.4 ohms offset would not be unusual. The switch you're testing is either open or closed, so if there is anything other than infinity, it's closed.

Those clamps on the intake runner couplings are by and large superfluous. The rubber couplers are such a tight fit that the boots end up being just for looks, especially a one-time crimped factory clamp that can't be tightened. You could add a clamp there in lieu of or in addition to the existing one, it won't hurt, but I would confirm a leak there first so you know you're fixing a problem instead of stabbing in the dark.

If you are concerned about a vac leak there, and vac leaks could contribute to your bucking problem so you should be, there is a common shadetree method to find leaks. Use some kind of flammable spray, or a propane torch without lighting it, and with the engine idling apply the spray or put the tip of the torch at each point where you suspect leakage. If there is a leak, the suction will draw in the flammable fluid or the gas and you will hear a noticeable change in idle speed upwards as the fluid or gas is burned. The results should be repeatable, as in if you hear a speed increase once, wait a bit and see if you can duplicate the result. Idle speed may vary enough that what you heard may have been a normal oscillation. But if you can make idle rise again and again at any points, then you know where to put further attention.

That said, in my experience these engines are not especially susceptible to small vac leaks. A leak would need to be pretty large, and hence easy to find, to cause pronounced bucking at tip-in. When leaks are that large, idle speed will normally rise and fall rythmically.

Another thing about your initial compression tests; I've found that simple CR testing can give wildly disparate results from one test to the next, due to some hydraulic lifters losing pressure at rest. So to do a reliable test, the engine needs to be fully warmed up with no lifter tapping audible whatsoever. Then I only do one cylinder bank at a time, running the motor a few minutes in between to be sure all lifters are filled. Even then a weak lifter that works fine when there is engine oil pressure can leak down and cause an erroneous reading because its valve isn't opening fully. For those reasons I almost never bother with standard compression tests on these motors, and rely instead on a leakdown test, which isn't subject to variability in valvetrain operation. You may well have low comp on those cylinders, but I wouldn't go tearing into anything until I had seen both the leakdown results and a cooling system pressure test.

Sun Jun 08, 2008 6:30 pm

interesting.....

I did two things at once and now the van is better but not perfect. I took of the distributer cap and rotor and cleaned them up, put them back on. And I 'pushed' the clamp on the injector boot somewhat into position, but not perfect.

So i decided to replace cap and rotor with almost new set from a previous tuneup on my other van. No difference.

This looks like it might be the injector boot. Gonna test for leaks in the next few days, I hear carb cleaner is good for this. If it end up being the boot, is it hard to replace? It looks cramped in there.

Gregor

[edit] where do I get replacement boots from, can't seem to find them

Mon Jun 09, 2008 8:52 am

http://www.van-cafe.com/vanagon_parts.jsp?pa=p&p=485751750&pct=1814005571&ct=1730515060

Fri Mar 30, 2012 12:13 pm

Dogpilot wrote: the infernal Throttle Switch for proper operation.

I have a question about setting the throttle switch (aka idle switch)...

The diagram above is not too clear on where the feeler gage goes, but it seems like the only place to put it is between the screw with red locking compound on it (that should not be moved) and the base of the throttle that it sits on. Bentley claims the gap must be between 0.05 and 0.1 mm.

My Van seemed to be running well but with a high idle, so I pulled the throttle body off (it had some big gaps from wear), so I bought a refurbed one from VC and transferred the idle switch to the new one.

I checked the idle switch on the old throttle body and it seemed fine re continuity and the feeler gage gap measurement.

But when I put the idle switch on the NEW throttle body, I cannot move the switch to get any kind of gap at all when checking with the feeler gage at that " red locking compound, do not touch" adjusting screw.

Any ideas on this?

Could that little round cam disc be assembled in the wrong position or something? (or can it only be re-assembled in the "right" way)?

Sat Mar 31, 2012 5:03 am

randywebb wrote:
The diagram above is not too clear on where the feeler gage goes . . . Bentley claims the gap must be between 0.05 and 0.1 mm.

You've got the feeler gauge in the right place, but you may have mis-read the inent of these instructions. There is no gap required. The "gap" only appears when you step on the gas.

The instructions above (using the feeler gauge) are only for the purpose of setting the TPS. When you insert the .05 mm the TPS should be signal that reads "off"/closed. When you insert the .10, at that point the the TPS should be sending an "on"/open signal. If yours doesn't operate this way you use the adjustment screws on the TPS to make it so.