90 Turbo diesel Revving like crazy after rebuild???

[evan]

Just rebuilt my 90 Jetta this week (new rings, gaskets, ect)  Pretty sure everything went good, set and checked the timing twice and maked sure everything was torqued to spec.  

Everytime i go to start the thing, it takes a few turns, catches and then in a matter of seconds starts revving to the point that it sounds like it's going to blow up!?

Of corase i shut it off right away, but can't figure out what to do about this.  The turbo starts winding up like crazy and it blows tons of mostly white smoke all over the place (I havn't clamped the downpipe to the exhaust yet).  The white smoke starts immediately and as the engine revs up it completely fills the air.  But I don't think there's any oil burning or it would be blue and black.

There are two things that I think might be wrong:

When i was honing the cylenders, I couldn't really do it properly so the scrapings on the cylender walls are more of a circular shape than a "V" or "X" shape... but i didn't over scrape the cylenders to the point there were big gouges in them.  

I wonder if oil is leeking past the rings and combusting causing the engine to just keep revving???  (just a thought)

The other thing is that my injection pump was leeking from the max power adjustment screw so when I had the engine apart I took it out and put some thread locker on the threads and put it back in the exact same position as it was before... (i know it was a stupid thing to do while i had the engine apart but that's what I did).  

Now, even when I turn the screw out (counter clockwise) the engine won't slow down.  I'm thinking there could be some thread locker stuck inside the pump but i'm not sure.

Any ideas where I should start to try and find out what the problem is.  I would love to hear any feedback.  

I remember a long time ago reading a post where a diesel reved out of control until the engine blew.   But I can't remember the cause of that.  I don't know if it's possible for oil to get past the new rings and rev the engine out of control???

Any ideas where I could take it in?  I'm in mississauga near QEW and DIXIE.  

I Just rebuilt my brothers golf two weeks ago without honing the cylenders and it runs fine, so I am wondering what could have gone wrong???

Thanks, Evan

[Dr. Diesel]

i believe that old post you're referring to was the twin turbo engine deo built. hehe.  one thing you could try would be to push the car somewhere you can drive it,  stick it in gear and let the clutch out as soon as it starts. then you can at least bring the engine speed down with the brakes. Drive it to seat the rings and eliminate the oil past the rings possibility. Don't forget you'll have to be quick with the key to kill the engine when you come to a stop.  I could stop by on my way to toronto monday afternoon/evening if you want. Shoot me a PM if you want.

[DieselsRcool]

Does the engine shut down with the key? If so then it's fuel pump related. If not, it's oil related. My guess is fuel pump. Did it do this before your rebuild?

[dieselpower]

hey
I had htis same problem when i removed the whole govenor mechanism. maybe yours is sticking or sumthing because without it working properly my would just rev up as high as it would go. anyway if you are capable of taking the pump apart try that and see if the govenor is sticking. thats all I can think of thats wrong.

P.S. does anyone have a link to the post explaining deo's meltdown. i tryed seaching for it but couldnt find it. thanks alot
mark

[evan]

Does the engine shut down with the key? If so then it's fuel pump related. If not, it's oil related. My guess is fuel pump. Did it do this before your rebuild?

Yes the engine does shut down with the key, that's the good news!  

No it never did this before the rebuild, (I was stupid to even touch the thing while I was rebuilding it) the last thing you want to do with a new set of rings is rev the engine through the roof!

I did adjust the max power screw about a week before the rebuild (just to get a little more power, and put it back and had to adjust it a bit to get it running right again.  It worked fine for a week, but it was leaking a bit of diesel, so that's why during the rebuild, I took it out and put some "Lock tite Thread Sealer" On it but it is very possible that some of that had loged it self inside the hole.  Even when I turn the adjusting screw several times counter clockwise (out) it makes no difference!  

anyway if you are capable of taking the pump apart try that and see if the govenor is sticking. thats all I can think of thats wrong.

Unfortunately i'm not really capable of taking the pump apart (lacking tools and knowledge)  but I'm taking Dr diesel up on his offer for some help so hopefully he'll have a better idea of what is going on.

P.S. does anyone have a link to the post explaining deo's meltdown. i tryed seaching for it but couldnt find it. thanks alot
mark

I don't have that exact one but here's another one called "My engine ate itself to Death!"  I laughed my ass off when I heard that... then cried!
http://www.vwdieselparts.com/forum/viewtopic.php?t=2407

Again, if anyone has any suggestions I love to hear them!  

Thanks, Evan

[andy2]

the only time I,ve had that problem was when I cranked the fuel screw in a little too far :oops:

[DieselsRcool]

Do you have the idle adjustment backed out all the way too?

[evan]

No it's not backed out all the way, but it's out enough that I know that it is either sticking or completley messed up.  The adjustment I am talking about is on the side of the pump (right side looking from the front of the car)  I've heard it called the Max power adjustment screw before and it has a piece of metal welded to it...(just so ya know what i'm talking about).

But i've tried it in several positions and always the same result, leading me to believe that if the problem is there it is probably stuck inside.  

Unfortunately, as of yet, I have no idea how to fix this, i'm gonna go out and try to see if I can play with it a bit and see if I can see if it's actually stuck.

Let me know if you got any ideas!!

Thanks, Evan

[evan]

So last night Dr. Diesel came over!  (Thanks Doc) and took a look at it and after a few starts and playing with the governer on the fuel pump, determined that is was probably a faulty pump.  

So I managed to get another pump that I am going to try to put in, and I think that should do it.  

Went to Princess Auto last night and got the "Magnetic Base With Deflection Guage"  It's a dial indicator but has no thread to thread into the pump, has anyone used this type before?  

Well I hope it works, I really need to get the car going.  Gonna put in the new pump tomorrow, (birthdays today) so i'll let you know how it goes!

[moosiah]

Hi Yes I've done this. I used  a magnetic dial indicator holder clamped on the iron pump head to hold my Yamaha/ peacock 5mm dialindicator..... I bought it in '73 to time my yamaha race bikes....... I think it's quite funny that this tool has been used to time stuff from a TZ 750 racer that does 185mph :lol:  to my diesel bunny that can't do 90... :cry: ......... You'll need a long extention that fits your dial,( to reach down to the pump plunger ) make sure that the dial doesn't hit the glow plug bus around the water bypass on the head when you turn the pump and check your zero over and over and over if you do your timing this way.... ( the voise of experiance)..... good luck!!!!!!!!     :wink:

[evan]

So now I've put in the new injection pump and primed the thing like hell and it finally cought and started to run!!!

But, it's smoking a lot!  I think the reason is that I just couldn't seem to understand the values for setting the injection timing...

I tried to set the timing using the dial indicator, but it is very hard to do using a magnetic base rather than a screw in adapter... so I know that the timing is off.  But by how much i'm not sure!  I have the bentley manual but I am no mechanic and it is very hard to figure out what they want you to do with the guage.  I moved the pump many times and it smokes consistently every time.  I'm gonna go out and try a few more times but I'm pretty sure that it will be the same.  Does it have to be "spot on" to not smoke???  I still have to road test it too so i'll have to see how much power the car has.  

Overall the engine sounds really smooth so I am happy about that.  

Any other ideas why it is burning so much diesel?  And i'm 99% sure that it's diesel not oil.

Thanks, Evan

[andy2]

it could be that the pump timming is advanced too far, that will make black smoke and can dammage your engine if its left like that so before anything get the pump timming done :wink:

[evan]

it could be that the pump timming is advanced too far, that will make black smoke and can dammage your engine if its left like that so before anything get the pump timming done

I think you're right on with that...

I think that I may have not lined up the pulley with the groove in the injection pump shaft closely enough.  I am going to take off the timing belt and check that.  

I figure that if I re-allign the pump pulley with the shaft I'll have a better chance of getting the timing closer.  

I'm gonna try Sunday morning so i'll let you know how it goes!

Evan

[moosiah]

I sounds like you don't have the timing right on the whole system.... I made my own tools ....... I got a piece of ally close in size to the timing groove in the cam and filed it on the top side to fit the cam groove, the inj pump locking tool can be a 14mm bolt ,,,,,,, and I used a magnet mount to hold the dial ind in place.......you do have a KEY in the inj pump shaft for the sprocket don't you It should only fit one way..... The cam doesn't get one....... I retime the whole thing every time I mess with it ........   :wink: you can also get the timing 180 dgrees off too ,,,, and the engine WILL run ,,,,,,, badly..... make sure the mark on the pump sprocket is next to the notch on the pump mounting bracket!!!!!    good luck !!!!!!  I've had to figer all this out on my own ,,,,,,,, no DR Diesels around here, just the internet and cheap parts at pic an' pull .....