Swap Update - Tuning not going well, could use more advice.

[RarlyL8]

Well I was back at it tonight. Didn't go well but progress was made. I removed the air cleaner and put a sock on the oil breather tube. The heat wave broke, temps in the high 70's. Car started on about the third hit. Now comes the problem.


The engine idles at 2000RPM. I could not get the idle to come down. The idle adjustment screw was fully closed. I opened it up to 1 1/2 turns with no apparent change in idle speed. The engine quickly got up to 180 degrees - I felt the oil cooler and it was HOT. So I shut the car down for a few minutes. Hit the key and it idled at 1200RPM. The idle adjustment screw would not idle it down any further. I began to check the timing but had much difficulty seeing the numbers. Then I checked the temp gage and the car was getting hot - about 9:00 on the gage. I shut it down. The engine spit back, like dieseling, just for a second and left a drift of oil smoke in the air from the sock on the tube.

I cannot adjust the timing with the engine running like this. Any ideas why it idles so high for so long? Is it the WUR?

What is the quickest method for checking the timing? Do I need a dental mirror to see these marks? My service manual isn't much help right now.

Thanks.

[RazorRacer]

Adjusting the timing is easy. Get a timing light ($30-40) at the auto store. Put the wire clamp around the 1st cylinder spark plug wire. The first cylinder is the closest one on your left hand side facing foward. Put the negative clamp on one of the stainless steel braids. Put the positive clamp on the 12V+ of the fuse block. The cover has to be removed next to access the fuse block. It's right next to the area you are working and only has two wing bolts to unscrew.

Start the car, point the light at the fan and you will see the marks.

Adjusting the timing will effect the idle.

Better yet, get a copy of Wayne's book.

[emcon5]

White nail polish on the timing marks helps a lot. I couln't see mine without it. I also can't see the Z1 mark on my pully without a inspection mirror and a flashlight.

Do you have a vac advance? Having the timing too far advanced could be an explanation for the non-adjustable fast idle.

Just a couple random thoughts, probably not much help.

Tom

[critter]

If it was my car I would retard the timing.Just mark your distributor so you know were you started and then start retarding it until you can get it to run cool enough to set the timing right.When you try to start it does it sound like it is fighting the starter when it fires? I would also think about richening it up a bit as it also sounds lean.If you write down how many turns you make on your mixture after you do it what do you have to lose? you won't burn a hole in you piston being rich and retarded.

Ps I am not calling you retarded but I am suggesting you do retard your timing.

[beepbeep]

Errr...critter:

Moderately retarded timing won't burn a hole in a cylinder, but severly retarded timing will ignite mixture too late, letting it burn partly trough exhaust and heads and heat up the engine just like he said. I think too much retard is his problem.

Rarley8:

I second RazorRacers advice...fix the timing first ... don't worry about the idle.

Fast idle can be caused but heaps of things. You can have vacuum leak somewhere, WUR can be bad...dump-valve seals might be leaking etc etc. , but it shouldn't run hot beacuse of that. Once you get engine idling (even poorly) without heating up like mad, you can concentrate on mixture, idle speed etc.

P.S.

All 930 engines diesel, they are made that way...CDI box is still on for couple of seconds when you turn off the key so engine can burn any remaining fuel left in the cylinders...nothing to worry about.

[RarlyL8]

Thanks guys.

I've been timing hotrods for years so I understand how it's done.
I have a list of what may be going on and was hoping one of you might suggest the same for verification and elaborate on it.

1- vacuum leak
2- throttle plate open slightly due to lincage bind
3- WUR? They usually work or don't work.
4- lean mixture
5- timing advanced due to high idle

The engine's bench timing was set at TDC. When I attemped to check the timing last evening I saw a line on the pully lining up with a line on the fan housing - just don't know which line it was.

SOOO - my next step? Using your suggestions I'm thinking:

1- turn the motor over by hand and paint the timing marks
2- remove the intercooler and re-check for vac leaks
3- remove the throttle lincage at the motor and check for binding
4- pull vac line off distributor, even though manual says leave on (Euro)

The static timing can't be too far off as the engine fires right up when warm. Looks like we might be getting somewhere.

[dickster]

RarlyL8

start with getting the basic static settings right.

fuel, firing order,etc.

the timing could be way off, set the static properly then you elminate that possibility.

and the spit back or "run on" may be a trait of 930's but its also synonamous (sp?) with bad timing.

what does the engone rev like? usually if the timings way off it won't rev cleanly.

whenever, i have reinstalled an engine (granted, not a 911 engine but principles the same), 9/10 if you get these settings right it'll run pretty good from the first turn.

i've got dme so can't help with your specific model.

hmo, good luck.

[beepbeep]

P.S.
You are using SC-cams, aren't you? OEM 930 cams are very mild, so you are introducing some other variables into the equation...as they are "hotter" than vanilla 930 ones...

And a stupid question: Are cams timed right when engine was put back together? Now this shouldn't happend but you never know...

P.P.S.
Also, recheck for vacuum leaks, my car idled @ 1300 RPM before i dug out intercooler and dump-valve assembly, replaced dump-valve seals and re-tightened all clamps (and there are many of them).

[RarlyL8]

The engine revvvs freely, too freely. It wants to hang out high and drift back down when I tickle the throttle. It sounds good. No missing, no unusal sounds.
This is one of the puzzling things going on. I also would expect rough running if the timing were way off. I don't believe that it is. The high idle may be caused by a vac leak which in turn causes the timing to advance which causes the oil to heat up........
Just my current theory.

edit - hey roadrunner, you're car is a Euro, do you check timing with the distributor vac line on or off? My manual says on for a Euro off for US.

Another question - when I quickly rev it up a bit the engine makes a farting sound when back off throttle. Is this the dump valve?

[beepbeep]

I don't know if timing should be set with vacuum advance off...but as far as i know vacuum advance is only there for complying with smog laws at idle, so it shouldn't matter that much. Personally, i would adjust it with a hose off/plugged.

"Farting sound" is typical, especially if you have free flowing exhaust system (if we are talking burbling/popping sound)...it's just unburnt fuel exploding.

Dump-valve in 930 is of recirculating type and cannot be heard unless it's seals are worn. In that case you'll hear distinctive "clonk clonk" when you step on accelerator as dump-valve piston hits the metal.

[Tinker]

Rarly,

My 930 behaved funny when one of the fuel pump relays (red ones) became partially dislodged. In additon to powering the pump, it sends voltage to the auxilary air idle valve. Without power to the valve, it will stick open and you will have a high (1,200+) idle. Turn on the key and make sure you have near 12v going to the air idle valve. Make sure the lines going in and out of the valve are good and not leaking.

Tinker

[RarlyL8]

Hmmmmmmmmmm.

Well the sound upon throttle lift is sort of a short pop/fart. Very short brief sound. The exhaust isn't particulary free flowing. I took that god-awful dump pipe off and fabbed up a stock muffler. The rest is stock Euro. Not loud, but not quiet either. The noise is NOT exhaust related as far as I can tell.

The auxilliary air valve and associated switch have been removed to simplify things (not simple enough apparently).

[dean]

The factory manual says for a euro 75 930 to set the advance to 29 degs before with the vacume retard disconected. I think you are retarded also. I bet you have to reindex your dist. so you can set the timing.
Paint the 3 marks on the pulley. Hook the plug lead for the timing lite up to the coil (6 times brighter) and time it at 4000 rpm. 29 degs is 1 mm to the left (or right) of the 30 deg mark.

Do you have a decel valve? That could be why the revs hang.

[RazorRacer]

I think you are retarded also.

Did you mean to say that?

Sorry, couldn't resist.

[RarlyL8]

Whyyyy you little snot bag. In myyyy day we respected our elders.


Hey guys! Good news!!


We did it!!!

I removed the intercooler and looked for vacuum leaks. I found the culprit. The line from the bottom of the intercooler to the WUR was loose!!! Also found another minor one and fixed it as well.

SO - I put the intercooler back on, hit the key ONE TIME and BAM she starts! Idle was sluggish at first and then rose to 1700RPM. I ran to the engine and retarded the dizzy to 1000RPM. Checked the mixture, fiddled with the idle screw, and tried to find the timing (for kicks). Well nothing was responding so I just let the car run listening and watching the temp gage. Took 10 minutes for it to get up to 8:00. I then shut it down. Aux oil cooler was COLD. Waited a few minutes and put the dizzy back to where it originally was. Hit the key and BAM she starts and idles @ 600RPM. So I adjusted the idle to 1000RPM. Played with the mixture screw - nothing I did made the engine sound or behave differently. Turned it RICH 1/4 turn, then back to 0, then LEAN 1/4 turn. Nothing. So I'm ready for a CO meter now (gotta give my buddy a call). I have no idea where the timing is but the engine seems to like it. Hit the key and she starts and idles smooth.

I am one happy camper today!
So to end the day on a good note I quit while I was ahead. Now I will color the timing marks and barrow a CO meter. I pulled the car into the garage UNDER ITS OWN POWER and slowly revved it to 4000RPM. It wants to rev quick! She is eager! When I shut it down (@1000RPM) the exhaust pops and I can hear the turbo spool down for several seconds after the engine has stopped. The fart noise is GONE. Must have been comming from the leak at the intercooler. The front oil cooler NEVER GOT HOT and the gage reached 9:00. Something is wrong with the gage, probably the 930 sender is incompatable.

Man I am relieved. I had visions of tight bearings from the rebuild causing low clearance heat problems.

I see a maiden voyage this weekend! Thank you guys and wish me luck!

[Bill Douglas]

Well done Rarly8 - and good luck for the weekend

[RazorRacer]

Originally posted by RarlyL8

Also found another minor one and fixed it as well.

Any idea what that one was?

Congrats on your fix.

[hilandscott]

Have a nice cold one and sleep well, dreaming of the maiden voyage!

Glad it was nothing you couldn't handle with a closer inspection...

[75'930cab]

Does anybody have a PIC of the WUR?

[RarlyL8]

I'm still taking lots of pix as I go. The WUR should be in one of them. Hope to post pix by Monday. The other (slightly) loose hose went to the vac retard switch that cuts it back under boost.

I am still on a high this morning. TWO YEARS I've been fiddling with this engine. I'm doing that "I gotta turbo" dance like that fella in the comercial dancing goofy in his undies. With little kids and a demanding job the hobby door is rappidly closing. The first time she comes up on boost you guys will be there with me. Video WILL follow.