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abuzar1
11-27-2012, 05:55 AM
First of I'd like to thank all the members here. I had a lot of car starting issues but thanks to you guys I got them sorted out. I had the car back to running, starting, and driving beautifully on regular ol' diesel.

After driving it for a few days I decided to just park it and sell it. Took a few pics and what not. A week later when I went to go start the car it was stuck on FULL throttle. I started freaking out and smoke started coming out of the engine compartment. I don't know what the smoke would have come from but I hope I haven't ruined the engine.

ANYWAY, so then I disconnected the fuel line to get it to stop. I noticed this one thing was broken. I was hoping someone could tell me what it was and where I could possibly get replacement parts from (for example if any VW cars use the same part and I could go to a salvage yard and get it from them).

Here are the pics:

http://imageshack.us/a/img27/1997/dsc0212jw.jpg
http://imageshack.us/a/img687/8031/dsc0213fq.jpg
http://imageshack.us/a/img51/1791/dsc0214ci.jpg
http://imageshack.us/a/img204/217/dsc0215ym.jpg

anders
11-27-2012, 07:42 AM
That's for the cruise control. I'm not sure if it is volvo specific or not. I may have a used one to sell if you have trouble finding one else where.

abuzar1
11-27-2012, 04:27 PM
Would that make the car rev up on its own? I forgot to mention, turning the key off did nothing. I had to disconnect the fuel to make it stop.

ngoma
11-27-2012, 10:15 PM
Sounds like you had a runaway. What did you disconnect? The wire to the fuel solenoid? The fuel hose itself? I don't think I would have the courage to reach into the engine compartment during a runaway.

kcfoxie
11-28-2012, 10:54 AM
Generally it's better to smother the air intake with your hand to stall out a runaway. Assuming this is a turbo, a blown turbo will leak oil into the intake. How is your oil level looking? Smoke color? A blown headgasket could also cause oil in cyls; but I think that's more rare than the turbo failing.

v8volvo
11-28-2012, 07:23 PM
I've had a similar runaway experience. I feel your pain! Hopefully the cause for your issue is more benign than what turned out to have caused mine. :o Let's see if we can figure out what happened and get it sorted out.

In your case, how soon after starting the engine did the revs begin to rise out of control? There are two types of runaway possible on a diesel engine - one is caused by excess fuel from an injection pump issue, and the other is caused by excess oil from an overfilled crankcase, failed turbo, or a situation of extreme blow-by. In either case, shutting the key off generally will not be successful in stopping the engine, since even in the case of a fuel runaway, once the pump is turning at a high speed and flowing a lot of fuel, the little fuel cutoff solenoid isn't able to push its plunger down with enough force to stop the flow of fuel. In the case of an oil-related runaway, of course, the fuel isn't what is running the engine anyway so shutting off key will have no effect.

A runaway fueled by engine oil, however, can generally only happen after the engine has been running for some time, usually at high RPM (as when cruising on the highway) and when the oil is warm and thin and has had a chance to get blown up into the intake system in quantities sufficient to eventually form the "critical mass" that initiates a runaway. It is close to impossible for that to occur promptly after startup, but it sounds like your runaway happened almost immediately after startup, which leads me to believe that it was a fuel-related runaway.
*edit, looking again I see that you stopped the engine by cutting off the fuel supply, which makes it certain that it ran away on fuel not oil...

Remember that the "starting conditions" inside the VE pump (i.e. the position of the fuel flow apportioning system when the engine is turning at cranking speed, or IOW very close to or at 0 rpm) provide for a good slug of initial "throttle" to get the motor running, since the governor is not spinning enough to pull the flyweights out at all and apply any real pressure against the control lever. As soon as the engine starts and the governor starts to spin, it shoves the control lever back a bit and pulls the engine down to its idle speed. However, if I remember correctly, this injection pump had vegetable oil run through it, unheated no less, right? If some of that turned into goo, and caused the motion of the fuel control collar to become restricted, then when the engine started the control collar could have stuck in place on the shaft, and not allowed the engine speed to drop, which might be what caused the runaway you experienced.

Or, alternatively, it could have been a situation similar to what broke my pump -- I think I remember that you also were dealing with an issue for a while where the engine wouldn't build revs and was hard to start, which we on here figured was being caused by some kind of fuel system restriction. What did you have to do to fix that? Did you figure out what was causing it? If it was indeed a case of air ingress or fuel restriction/starvation and it was operated that way for any period of time, that could have caused the suction pump to grenade and send metal chunks downstream. That can be the start of a sort of domino effect failure, with one of the possible results involving the metal bits jamming the fuel control collar on its shaft, ripping the ball stud off the end of the control lever, and disabling all engine speed control. That is what we found when member ngoma and I did an autopsy on my failed pump, and we have since become aware of at least one other case in which that happened in a VE pump. In that case, it was a pump that had also seen vegetable oil -- perhaps coincidental, perhaps not...

So, there are a few possibilities. As to how to proceed forward -- here is what I would recommend as a starting point. First, and most important: DON'T start the engine again until after it has been diagnosed and repaired, even just to try it. You don't want to run the motor again unless you *know* for a FACT that you have FOUND the issue that caused this to occur, and SOLVED it with 100% certainty. Running a cold engine at top speed can have very bad effects, and it's also potentially damaging to the automatic transmission. Number one objective at this point is to not let the IP issue cause any collateral damage. Don't go near the ignition key until you know the problem is fixed.

Second, start by checking the simple things on the outside of the pump. Is there something that is keeping the throttle lever from returning to idle position? Is the return spring intact? Any other changes visible externally? Look hard and carefully, because if you find nothing here you'll have to go inside the IP, and you don't want to do that if you don't have to!

Third, if you don't find something external that can be easily resolved: get a high-quality ball-end 5mm Allen bit, and remove the top cover of the injection pump. (This requires some other steps such as taking apart the throttle linkage, etc, you can look for guides online to take you through those). Be very careful about letting any dirt or grit get inside the pump. Once you've got the top off, look down into the pump and see what is going on in there. Is the end of the control lever still present and engaged with (and able to move) the control collar, or is it broken off and missing? Do the pump's internals look corroded? Any shiny metal powder floating around inside? What's the status of the fuel in the pump? Is it good clean diesel or biodiesel, or is it sticky rotten VO, half water, etc?

Based on the answers to these questions you'll be able to figure out what your next step will be. If parts are broken then the fuel pump is hosed and it will have to be replaced or professionally overhauled. If it's corroded or gooey or full of bad fuel, then you might be able to carefully unstick it and get it working again. There will be no way to know exactly what the situation is, unfortunately, until you get a look inside the pump.

Let us know what you find and we'll try to help. It's too bad these engines don't have a key-operated throttle valve that snaps shut when the key is switched off, like later TDI engines do. On those they call it an "anti-shudder valve" since its main job is to smooth the normal diesel shut-down jitters (and on the most ones additionally provide some manifold vacuum under some conditions to pull in more EGR), but it serves a secondary purpose of throttling and stopping the engine in the case of a runaway. Clever idea -- every diesel engine should have one! :rolleyes:

George

745 TurboGreasel
12-09-2012, 05:56 PM
Generally it's better to smother the air intake with your hand to stall out a runaway. Assuming this is a turbo, a blown turbo will leak oil into the intake. How is your oil level looking? Smoke color? A blown headgasket could also cause oil in cyls; but I think that's more rare than the turbo failing.
DO NOT use your hand, it is better to sacrifice an engine than a limb. A board across the turbo inlet works well.

another possibility is the CC part(or another foreign object) fell behind the throttle mechanism, not allowing it to return.

abuzar1
12-16-2012, 11:00 AM
Sorry I kinda disappeared for a while, I didn't really have any time to check it out.

So the throttle mechanism is not blocked or anything. It returns just fine. I'm not skilled enough (nor patient enough) to take apart the throttle stuff to get to the IP. I might just hire someone to do it for me and see if they can figure it out, if not ill take pictures and report back.

ian2000t
12-20-2012, 02:03 AM
Interesting reply George. As you know I run my car on veg oil (with 15% unleaded), and one thing on my to-do list is to increase the fuel line size from the tank, as currently at high revs I feel some restriction (or air being drawn in maybe due to high suction).

I think after reading this it is DEFINITELY going to move further up my to-do list!! :eek:

I also have a second hand (supposedly good condition dry stored) pump to rebuild for mine (my pump leaks). Could you post any pictures of the pumps you took apart, as one thing I have been concerned about with fitting a second hand pump is potential run away, like in this thread:
http://d24t.com/showthread.php?t=677

abuzar1
12-20-2012, 07:18 AM
Man seriously screw volvos lol. I've got 2 other ones that aren't working right. I've got a 760 Turbo Intercooler and V70 XC. The 760 wont rev past 2500 rpm when you're driving and yesterday it wouldn't start. Timing belt broke. The V70 won't rev past 3500 rpm lol. Drives great on the highway even at 70mph if you take it easy and let the car shift early because once it hits that 3500 rpm its not going anywhere till you back off the throttle.

PS guys if I dont wanna mess with re-building the pump and what not what other cars have interchangeable IP with this car? I'm thinking of hitting up the junk yard and just having someone do a simple replace vs paying someone lots of money to actually rebuild.

ian2000t
12-20-2012, 03:02 PM
I think the only place you'll get a suitable IP is from a VW LT Van diesel. IIRC all of the other 6 cylinder diesels with Bosch VE rotate the opposite way (i.e. Cummins?).

745 TurboGreasel
12-22-2012, 03:02 PM
PS guys if I dont wanna mess with re-building the pump and what not what other cars have interchangeable IP with this car? I'm thinking of hitting up the junk yard and just having someone do a simple replace vs paying someone lots of money to actually rebuild.
it should cost you maybe $30 to reseal yourself.

v8volvo
12-23-2012, 10:32 AM
it should cost you maybe $30 to reseal yourself.

Don't think reason it's running away is because of a leaky seal.... would be nice but I doubt it.

Abuzar, the trouble with your idea of getting a junkyard pump and having it put on is that in all likelihood that is not practically possible... first of all, finding an intact D24T injection pump in a junkyard would be a small miracle; second of all if you do find one there is little chance it will be immediately in useable condition, will likely require new seals at the least...

and third and most importantly, there is no such thing as a "simple replace" when it comes to an injection pump on this or any other diesel engine. Very unlikely you will find anyone who is willing to even touch it, let alone someone who has the special tools and knowledge required to do the job. Unfortunately, you can't just bolt it on and drive it away, the timing has to be set which requires tools and procedure that can't be fudged. There's no shortcut, period... keep in mind that if it's not done *exactly* right, at best the engine will run poorly, and more likely it won't run at all.

You can call around to some junkyards and see if any have a diesel Volvo there, and call around to some Volvo or VW specialist shops and see if anyone is willing (and able!!) to put a pump on -- worth a try anyway -- but my best guess is that you won't find any luck on either count. These cars are rare and professional mechanics capable and willing to work on them are even rarer.

Your easiest approach here, I suspect, will be to figure out what went wrong with your pump yourself, and repair it from there. Truth is that fixing an issue like this is not really difficult as long as you have the knowledge, tools, and above all the patience (i.e. you're not a mechanic trying to make flat rate on a job they've never done before!). You probably have the time, and we can gladly help you on here with the knowledge and the tools...

How about some pictures of your throttle linkage? :)