Smoking and running rough

[burn_your_money]

You may as well send it to all of us, I think we all like to laugh While I have no experience using oil for a compression test I do know that the bentley suggests it so you probably are fine

What weight of oil are you running? that could give you the bad starts you are describing (needing to be plugged in at 30)

Has all of this happened over the same tank of fuel?

You can't really test glowplugs accurately with resistance or by continuity (test light) because they can fail in a closed state. Even if the glow plugs are new, if they were over torqued during install that alone can kill them right there, if not within a few hundred miles.

I think you have 2 separate issues though, one is the hard/ bad starting and one is the smoke. If it was the same issue it would go away once the engine warmed up.

Any word on your cooling system?

[Vincent Waldon]

The compression test with oil is directly from the VW service shop manual. I know it can ignite and some folks even tell about how they blew their motors up doing it. VW has been using this as a test for over 20 years now so I can feel confident with reason I will be OK.

I only clarify this 'cause it's a potential safety issue... obviously we're all big boys and can decide what to do.

The VW service manual (the Bentley) actually specifically warns against doing the oil test on diesels... here's the text from the MK2 version:

Wet Compression Test (gasoline engines only)

To analyze poor compression and further identify the source of the leakage, repeat the compression test, this time with about a tablespoon of oil squirted into each cylinder. The oil will temporarily help seal between the piston rings and the cylinder wall, practically eliminating leakage past the rings for a short time. If this test yields higher compression readings than the "dry" compression test, the difference can be attributed to leakage between the piston rings and cylinder walls, due either to wear or to broken piston rings. Little or no change in compression readings indicates other leakage, probably from the valves or a failed cylinder head gasket.

CAUTION-

Do not attempt a wet compression test on a diesel engine. The oil in the cylinder may be ignited by compression pressure.

Again, I only clarify this since it's a potential safety issue.  I personally do lots of things the manual tells me not to... like messing with the injection pump, for example  ;-)  YMMV  I personally think the odds are slim... but that's their word on the subject.

[burn_your_money]

Quoting my Bentley

to determine whether the piston rings are causing low compression, squirt a small quantity of SAE 40 oil into the low reading cylinder(s) through the injector hole(s), and repeat the compression test

- Volkswagen Rabbit, Jetta, Diesel Service Manaul

[Vincent Waldon]

Cool... MK1 vs MK2 eh....


Dueling Bentleys at 40 paces, anyone ??!!!  ;-)

[burn_your_money]

maybe someone sued the Bentley company so they revised the mk2 version

[mtnsammy]

Someone posted a PDF file on the shop secret manuel. It has great info and it also tells about the wet test. I think just like any other manual if the common shade tree mechanic was to do it with out knowing how much and how ofter it would be like lighting the propane heaterafter the spark failed without letting the gas vent out first. Many get lucky and some have to grow new eyebrows. 30 years wrenching and I still have to grow eyebrows sometimes.

I got my primary car running again today so I should be free this weekend for the test. I will post the pictures on the Suzuki site since I know how and link that to this site. In my mind this made sense???

[Vincent Waldon]

Yes, pictures please !!!

[mtnsammy]

OK here is a link to another post of the Samurai trucks with VW Diesels
There is a picture of the exhaust in the post.

http://bbs.zuwharrie.com/content/topic,75775.0.html

Later tonight I will pull apart the injectors and redo the compression check. Tomorrow I will post those results as well as pictures of the injectors and glow plugs.

[KTMAuto]

Had the same problem.  The smoke turned out to be unburnt fuel.  Not black 'cause not over 2500 combustion temp.  Just raw white smoke.  Knowingly, ran some free fuel contaminated with gas.  It was pretty diluted maybe 1 to 10... So the fuel was flat under power, but free.  The next tank of real fuel the motor started chug'in and smoke'in, white at idle.  Random miss fire.  Up top it burned clean (almost to clean), smoothed out.  Took the top off the pump and found the gas worked as a solvent.  It had broken free the thin layers of what looks to be the fuel staining on the inside of the  pump.  I ended up taking the pump apart to clean complete.  I think the problem was in the very top off the pump.  The star looking wheel with the four weight, maybe the governor, had some gummy residual under the weights that would not let it to retract all the way.  U sound capable, pull the pump apart.  I have saved a few pumps by going in a finding something wrong.  Good luck

[mike71ghia]

I suspect not wanting to crank has more to do with the low compression you have. You don't mention what machine work was done, Did it get bored and new pistons/rings ? Valves faced or seats cut? Did the shop have the head? You're low on compression for some reason now, if it was bored and honed the honed crosshatch may be too rough allowing blowby and needing additional breakin time, if the valves and/or seats were reworked and they didn't have cam & followers or didn't check the new installed height you could be loosing compression charge past the valves..but is easily checked as your valve clearance standard procedure...you mentioned they rebuilt the injectors also, I'd atleast check the pop pressure and make sure of a spray not a stream. Bosch nozzles are very reasonable on ebay if they only cleaned yours.
Oil test is ok with common sense, but liquids don't compress hence the warning... only use ~1 cc of oil, on FLAT GROUND so it can seal ALL around the ring and give the oil time to get there... find something similar to a piston and watch how long it takes oil to runoff..where it would rest on the top rings where it does the sealing. If you find the comp has come up significantly the rings aren't doing their job, I doubt this is a pump prob if it will make enough power to drive reasonably but with white smoke...

You can tell a lot about leakdown by placing in 3rd or so gear on a hill with a partner and use a hose to listen into the crankcase through the oil fill and through the intake manifold, push downhill just enough to hear the air hissing from leakdown. Exhaust leakage is a little harder to hear, and for safety sake stay on the uphill side with the end you want to listen to.

[mtnsammy]

Motor work was complete machining. The head was checked hot for leakage and the valves were ok. The cylinders were cut and I do not know the ring size used. I am heating up the garage now so I can start work. I luv lazy sundays. The way she is running now I have no power and a lot of smoke. New post in a couple hours.

[mtnsammy]

Hate to sound like an old fart.... In my day the machine shop was always right. I never questioned a machinist. Hi sopinion was based on exact measurements and precise machine work. Everything was written and documented. Quality German in SoCal and their machinists are worthless. 7 shop reworks 4 heads and still I have a pile.

New plan;
Compression test is 250 dry and 450 wet. Sorry waldon even at those numbers no big bang show. Glow plugs look new and injectors have minor carbon on them. Compression rings??? TOAST.

I will now have to rebuild the motor myself and find where the machinost did not measure or cut. At least the heads are not blown or cracked. Something was not or has not been checked with the cylinder bore. Whether it is out of round, tapered, or just cut sloppy the rings did not set and I never achieved full compression.

So if any real machinists are out there and can tell me options for cylinder bore as well as specs for max cut and resleave requirements I will be very happy. Possibly I have a shop in LA (78 mile drive ) or Las Vegas ( 188 mile drive with dinner and a show ). If anyone knows a better shop let me know. I live in Big Bear 92314 for Google maps.

The Vegas shop is a part time neighbor of mine and is supposed to be the largest in Nevada. Don't know the name but he drives real nice cars and his toys are tops so at least he has made good bank for the past 30 years he has run it.

[jimfoo]

That sucks. Keep Total Seal in mind for rings. You can get a whole set, have your second ring machined or buy just the 2nd rings from them.

[mike71ghia]

Have you taken the head off yet? Even a cheapo $30 dial bore gage will help you a LOT.
http://item.express.ebay.com/2-6-BEST-CYLINDER-BORE-GAGE-DIAL-0005-GAGES-GAUGE_W0QQitemZ260204505403QQihZ016QQtrZexpQQcmdZExpressItem
or search dial + bore on ebay.

If they bored it and used standard pistons they will surely chew the bore and rings...from the piston rocking
Machinist used to mean something... nowdays it often means HACK
If the machine shop is reluctant to discuss surface finish and fit tolerance with you it's the WRONG shop. If the music is louder than the machines it's the WRONG shop.
The first indication was their thinking 500 psi is too much, but a diesel or gas bore & hone job should be something any shop should get right and if you return to discuss it with them it's something you should put in their lap.
G'd luck with the Sammy, I drive a TD Isuzu Trooper!

[jimfoo]

In Ca, the land of the lawsuit, I would think you would have some recourse for a crappy rebuild.