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  #11  
Old 11-19-2009, 10:02 PM
v8volvo v8volvo is offline
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I still have the 157k car, its motor is pretty far gone but I'll be installing my good spare one at some point this winter, whenever that elusive free weekend turns up... Is yours the one that was advertised on CL for the past several weeks, down in Tacoma IIRC a light blue or silver sedan with blue interior?

Regarding the engine running problems you described: Could be injectors, or they could at least be a contributing factor, but there are several other possibilities as well. One is valves -- they probably have not been adjusted in ages and may be out of spec. Misadjusted valves can also contribute towards smoke, poor starting/running, and low power. They are easy enough to check, just need a set of angled feeler gauges. If they need adjustment, that's more of a job, requiring special tools and a set of shim discs of varying thicknesses. I have all that stuff so can help out if you get to that point with it.

Make sure your glowplugs are a matched set. If you don't know what kind are in the rear 3 holes, then put in the same type you installed in the front three so they can be ruled out as a possible factor. Mismatched brands/types of glowplugs can cause all kinds of running issues, including major engine loping due to uneven compression from unequal-sized tips taking up varying amounts of volume in the combustion chamber and causing uneven engine compression. Ask me how I know.

I have had OK results with injector cleaner products in some cases -- Diesel Purge is a good one, made by Liqui Moly -- but at the end of the day injectors don't wear out just by becoming dirty. The physical metal parts themselves wear down, and running a cleaning product won't fix that. After 170k, they should be rebuilt. If you have a pop tester, then you will be able to make sure they are all matched properly and have a good spray pattern. That will help the engine run better in every way. The only time I have seen injector cleaner really help is when someone has done something dumb to their engine, such as running unfiltered and unheated veggie oil in November like happened to the poor Mercedes that got towed in a couple weeks ago. Don't do that. If you do, BG or diesel purge will help clean up the mess, but my guess is that in your case they are just plain worn out.

Finally, here is the big one: timing. You are right that most shops had no idea what they were doing when they worked on D24T engines. Replacing a timing belt on a D24T is not a horrible job but you have to take some extra steps to make sure it gets timed right. Most shops don't take those steps -- they just slip a new belt on and don't worry about it. That causes the engine to start and run much worse. Timing would be the first thing I would check. If you don't have the tools or know-how to do it, let me know and I'll find a way to help out.

If you get your timing, glowplugs, and injectors sorted out, and assuming the engine compression is still solid, then I think you'll be much happier with the way it runs. I'm happy to give it a look-over some point; shoot me a message about setting up a time. What part of town are you in?

Local parts sources around here are tough -- at the shop we can get parts through IMC which has a good selection, other than that there's Ravenna Volvo, which I don't mind supporting, and Abe at MBMW Parts is a good guy too. There's Bow Wow in Lynnwood for VW parts, but they are not great on Volvo stuff. For Volvo body/chassis/interior items Northern European in Ballard has everything but they are not cheap and have almost no D24T stuff.

Don't forget to run sustainable biodiesel in it -- Dr. Dan's in Ballard is the place to get it. Better for the car and for the environment.
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  #12  
Old 11-20-2009, 11:32 AM
ngoma ngoma is offline
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Yes that's the car.

Injectors were last checked May 2007 143,000 miles, apparently got the OK.

Valve adjustment: Records show head gasket replaced May 2008 158,xxx miles. Repair invoice calls out $475 sublet "Machine Shop Rebuild Cylinder Head," hopefully this included valve adjust. New HG looks to be a 3-notch fiber type, invoice shows new bolts. Retorqued 1200 miles later. Is it worthwhile checking the valves again, approx. 15,000 miles later? Can the VC gasket be reused? Previous valve adjusts: May 2007, 140,000 miles, Nov 2003, 85,xxx miles, Oct 2006 65,000 miles, Jan. 1989 33,xxx miles, Mar. 1987, 17,xxx miles.

GPs are a matched set, as far as brand/pn: Bosch 0250 201 032, but different ages. #1,2,3 are brand new, #5,6 replaced May 2000, 65,xxx miles. GP #4 (along w/ #1,2,3) was replaced Nov 1997, 58,xxx miles. Given that #4 currently tests OK, could it still have eroded to the point it is affecting compression?

Compression tested recently June 2009, 170,xxx miles.
385 400 455 380 400 395, might be worthwhile pulling GP #4 just to see if there is correlation there.

Found a local source for the vac pump mount o-ring, ($2, seems reasonable enough, we'll see if it's the correct shape) Larrys Volvo, pass right by it to/from my daughter's school.
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  #13  
Old 11-20-2009, 06:47 PM
v8volvo v8volvo is offline
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Yep, Larry's is a good shop. They are the only other shop in town besides ours that has the correct tools and know-how to work on diesel Volvos. I will be interested to know if the O-ring you get is the right kind -- let me know. Those guys have been the only show in town as far as Volvo diesels for a long time so they may know some things that the rest of us don't in terms of getting parts, etc.

If the valves were done when the head was at the machine shop (which they should have been), then they are probably OK but it doesn't hurt to check them. If your valve cover gasket is the 1-piece rubber type it can be reused forever. If you have the old 4-piece cork kind it's worth upgrading to the rubber type anyway since it doesn't leak.

Glow plugs don't erode, so if yours all match then that's not your issue. The compression readings are on the low side, though. My '86 wagon with 271k was right in the same ballpark as yours, maybe a tad higher (I think there was only one cylinder that was in the 300s). My '83 764 had all 6 above 500psi when I checked it a couple weeks ago. The compression could account for part of the running issues you're seeing. If you don't already have synthetic oil in it, you might try running some fairly thin-grade syn (5W30) for a while and see if it helps free things up. If it has been run on dino oil its whole life the rings are probably pretty gummed. Lubro Moly makes a 5W40 semi-syn "Anti-Friction" oil that might also be worth a try. It has some kind of molybdenum or other kind of special substance in it that gives it a sort of silvery appearance right out of the bottle, kind of like it has anti-seize mixed in with it. Looks scary but it had a positive effect on an '84 244 Diesel with weak compression that now runs strong, so might help yours out too.

Sounds like the car has really been looked after. It's always nice to get a fat stack of receipts that show someone has cared about it. Who has been doing the work on it up to now?
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  #14  
Old 11-20-2009, 09:24 PM
ngoma ngoma is offline
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O-ring is thin and oval-shaped.

Do you check compression cold or hot?

Have a few invoices from '90s-- Jim Fisher Volvo of Portland OR. 2000 to mid 2008 was Larrys Independent. Last two invoices Summer 2009 were Louis Foreign Car Repair. This was who did the recent comp test and worked on the GP system. Oil changes since 2003 were done by previous owner, usually 2-3000 miles, since 2006 he used a blend of synthetic/dino.
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  #15  
Old 11-21-2009, 09:18 AM
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Jason Jason is offline
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You could also try BG 109 I think is the PN. Its supposed to dissolve carbon and gum build up and free up rings. May be something to think about. The compression readings are pretty up and down across the board.

Jason
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  #16  
Old 12-01-2009, 01:48 PM
ngoma ngoma is offline
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Took advantage of some good weather and installed the vacuum pump o-ring. It was leaking because there was no o-ring in there! Area now looks clean after a quick roadtest. Also the engine seems to idle smoother, although quite a bit of white smoke at cold startup and also if just let idle several minutes after cold startup. Warms up quickly while driving. The GP system apparently does not have after glow, is this true?
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  #17  
Old 12-02-2009, 05:19 AM
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Yes once it goes off thats it. There isn't a timed on and off like the newer TDIs and whatnot.

Jason
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Back again with a '84 760 GLE D24T/ZF

SOLD but not forgotten! 1984
760 Sedan, built D24Tic/ T-5 swapped

My engine build: http://www.d24t.com/showthread.php?t...t=engine+build
T-5 swap: http://d24t.com/showthread.php?399-W...to-quot-w-pics!
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  #18  
Old 12-02-2009, 08:51 PM
v8volvo v8volvo is offline
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Yep, it only lights them up before and during cranking, then for about 2-3 seconds after it starts, but not more than that. I have one aftermarket glow plug relay that does run them for longer, and runs them when the engine is hot too. It aids starting on tired engines. However, I prefer to have the plugs run less if possible, assuming the engine is in OK shape, so I took it off (my compression is good).

Larry's is a good shop and they know how to care for diesels. I would be reassured to see receipts from them -- the car was in good hands.

Compression can be done cold or hot, should not make a huge difference as long as valves are in proper adjustment. However, it is good to have at least run the engine somewhat recently, so that the rings are lubricated and achieving correct seal, etc.
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