Diesel Vanagon overheating

[ZanaEvyPapa]

Hi all,

symptoms:
Engine Temp- gets up high and temp light starts blinking when approaching 60mph

noise- theres a horrible shearing noise when engine is cold at startup(last for about 30secs. I originally thought it was a loose belt, since the noise is similar, but there's more of a grinding noise than a whinning noise. Anyhow, after I tightened the belt, the noise went away for 2 startups and then returned.

instrument panel light - not sure if this is coincidence or not, but the panel light that comes on at startup. The one of a line going in a loop. I think it's the glow plug light, not sure, but it looks similar to this one:[img]http://t1.gstatic.com/images?q=tbn:ANd9GcSzDjpd9fSLHcPTcK7XAy2SC2GnXAKmRgkMxzhofz3XCy6niQfJ&t=1[/img]
although I think it's only one loop, not two. Anyways, this light comes on at startup and coincidentally? turns off at the same exact time the loud grindy whiny noise shuts up.

Any clue?

Thanks,
Daniel
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82 Diesel Westy
03 Jetta TDI
Gainesville, FL

[Captain Pike]

STOP trying to start the engine. Take the timing belt cover off and see WTF is going on there.
If the belt snaps or the tensioner fails it will destroy the valve train.
I'm thinking tensioner.
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LEARN TO SELF RESCUE
59 Panel bus, 1966 Single cab. 73' 181. 73 Westy. 91' H6 Vanagon 3.3L.
....Bad Sneakers....

[strawhouse]

Just a thought, take off your water pump belt and see if the pump shaft is loose... maybe the pump is on the way out?
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Pacifist with a gun

[BrickFan]

A vanagon with a stock 1.6 diesel motor is turning a lot of rpm's when you are driving at 60 mph. That little motor is screaming at that speed and it will not last long. Although a lot slower, 50 is a more comfortable speed for the 1.6 vanagon.
The yellow light with the wavy line is your glow plug light. You are supposed turn the key until the light comes on (the "on" position) and wait to start the motor until after the yellow light goes out.
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'86 syncro
'82 westy diesel 1.6 n/a

[ALIKA T3]

I would re-do the air bleed correctly first.

If it boils in your expansion tank,you might want to check for CO2 fumes in it,if it turns green with the tester,your cylinder head gasket is bad and possibly the head too....
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Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[mwsnow]

Temp gauge reading high and high engine temps are two different things. The gauge is designed to blink and read high (all the way to the top) when the circuit is interrupted, so a bad wire connection looks the same as a overheating condition. The sensor is located on the side of that heater hose flange, on the front (looking from the rear of the van) end of the cylinder head. It should have a black/yellow wire attached by a spade connector. Clean/repair the wire connections as required. The sensors do fail, but not as often as the wire connection. If that doesn't fix the high temp reading, check the actual engine temp using an infrared gauge on the thermostat housing. Always ensure that your radiator is full of coolant.

Previous suggestions to check the timing belt and tensioner are good advice. When people buy gasoline vans, somebody usually chimes in immediately that the fuel hoses need to be changed. The diesel equivalent is to inspect the timing belt and tensioner and set the injection pump timing. As with the aforementioned fuel hoses, failure here is very expensive. New parts are less than $100.

Through three diesel Vanagons and a diesel Golf, I have found that odd noises usually come from the alternator. The diesel vibration eats them up. The early 65 amp alternators have fairly small bearings, which compounds the problem. Check the water pump, for sure, but be prepared to replace the alternator. While you have the water pump and alternator belts removed, try starting the engine briefly to see if the noise disappears. Reinstall the water pump belt and try again. Add the alternator belt and try again. When does the noise reappear?

If you don't have an owner's manual, try to find one. Proper starting procedures, including the function of the instrument cluster glow plug indicator, are in the owner's manual. Basically, you wait for the indicator light to go out before starting the engine. You should also have a Bentley service manual. Even if you don't plan on doing any of your own repairs, I doubt that many shops will have the service manual.

60 MPH is not too fast to run a diesel Vanagon, though you may not be happy with the engine noise. A complete and serviceable air intake system makes a huge difference in the noise level. '82 diesel vans came with two different transmissions, codes DM and DZ, with the DZ geared lower than the other. The injection pump contains a rev limiter. The speedometer is marked with orange dots for upshift points. It IS possible to downshift at a speed to high for the lower gear and over-rev the engine. With a van this old, it is very common to have a non-stock transmission, so don't rely completely on the speedometer markings. Still, you cannot over-rev the engine by any method other than downshifting.

[WAgrower]

Agreed that you should check out the timing belt and tensioner before trying to start it again. Mine was rubbing off and on and sounded like a soft rubbing.
Check by pulling the tensioner off and you will see a shinny spot or ring on the metal timing pan behind it. If so I fixed mine with a rubber mallet and a long bit of lumber. I doubt it is this if the sound goes away when running, but it's an easy check and a simple fix so start there.

I would put my money on the H2O pump and/or thermostat. They go bad and sound like hell if the bearings fail. The over heat could be caused by a faulty thermostat that's stuck closed ( that could have damaged the pump as well). One way to tell is warm up the engine and stick a thermometer in the coolant tank, it should read about 200deg F if everything is running well. Also the coolant pipes running to your radiator should feel warm, indicating the thermostat has opened and is working. You could simply have an air bubble in the system too... SO many things on a diesel coolant system

Also 60 mph is pretty fast for the stock tranny; do you have a conversion from a gasser? I've got the tranny from a gasser van and cruse at 70 pretty comfortably.

Hope you can track it down before it damages anything!

[ZanaEvyPapa]

another clue that I failed to mention:
The water tank right behind the license plate is consistently empty. I keep on filling it up and it just goes bone dry after a few days. The ooolant tank to the front passenger side of the engine compartment seems to stay at the same full level regardless.

Thanks for all the advice y'all. Yes, I agree 60mph is on the high end for this van. I typically run it between 50 and 55 mph. I'm perfectly comfortable cruising at this speed, and thank God, my wife is too. Even approaching 55mp, the temp gauge runs 75%. The van engine and tranny are stock. It had an engine rebuild about 40,000 miles ago, currently at 192k.

Anywhoo, I decided I'm slightly over my head on this one. I typically like to figure this stuff out on my own, but this van is new to me and I'm broke on time, so I decided to take it to my trusty VW diesel mechanic who, I just found out today, has been servicing this van for the previous 2 owners spanning back 15 years. He's also going to give it a once over since it's new to me.

brickfan, thanks for your startup advice. I've always cranked it from the getgo and not waited. My Jetta TDI has that light, but it goes out instantly, so, I'm spoiled. I will wait now. Probably get rid of my rough starts.

mwsnow, Indeed, I don't have the owner's manual, but I do have the Bentley.
When you say "A complete and serviceable air intake system makes a huge difference in the noise level.", are you talking about the stock system, or a mod? can you explain? Also, thanks for the advice on the revving. I wondered about that. I got it up to 70mph on a downhill and was worried. Could I overrev it in that case? Shortly after i did this stupid thing, I saw the red marks on the speedometer and almost crapped my pants.

WAgrower hmmm, that gasser tranny sounds nice. How is your acceleration? better or worse?

I'll let you all know what I hear back from the mechanic tomorrow. I'm guessing, based on everything I've gathered to this point, that I have a bad water pump and air in the system.

thanks again
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82 Diesel Westy
03 Jetta TDI
Gainesville, FL

[mwsnow]

The coolant overflow tank behind the license plate is connected to the coolant expansion tank by a rubber hose. If the hose leaks, you will lose all of the coolant in the overflow tank. I have driven for many thousands of miles without the overflow tank installed. The expansion tank (pressurized) is the important one. There should be little air in it, even with the overflow tank disconnected.

My comment about the air intake system refers to the stock system. Beginning at your air filter box, you should have a rubber elbow that connects to a rigid plastic component that sits in the space behind the left tail light. That rigid component is an air/water separator that helps to prevent rain, etc., from entering the filter box. From the air/water separator, an oval hose runs up the rear corner of the van to another plastic piece mounted behind the air intake grill, up at eye level. This piece allows the system to draw high-pressure air from the rear of the cavity, and also gives additional opportunity for water to be separated from the intake air. This is a tuned system. I have seen direct evidence of up to 5 MPH difference in top speed (1.6D Westy, DM trans, pedal to the floor, level ground) with the system installed vs. missing. The intake system also muffles an awful lot of noise. I think the oval hose is the most important part for noise reduction, but all of it is necessary. FWIW, I have found that a turbocharger (in addition to other obvious benefits) is the most effective intake noise reducer.

It is possible to over-rev the engine by letting the van run too fast on a steep downhill run. You can figure out the engine speed at a given MPH and transmission gear if you know which model transmission is installed in your van. The Bentley shows where to look on the transmission for the model code.

[WAgrower]

My tranny is from a gasser van that was put in by the PO when he put in a new 1.6TD. I gotta say the acceleration is ok; this is my first vanagon so I'm not sure what a stock set up is like. I was preparing myself for a snail when I was looking for one, but pleasantly surprised when I drove it.

1st gear is LOW, I find I have to shift at about 5mph! and 2nd is almost too tall to start in so I only use 1st when coming out of a dead stop. 3rd and 4th feel right where they should be, I can get on a freeway with little issue. SO You'll never win the 0-20 race with this set-up, but you also wont be honked at as much when getting on the freeway.

Hope your van comes back with a clean bill of health! I've had mine for 3 months now and it's been a fun journey getting it running and camping ready!

[mwsnow]

[WAgrower]

I do have a diesel tach but it's not working currently; still have to make a run from the z terminal.

I may be off; the van is still new to me and I hadn't driven it for a few weeks but today I was out and would say I could get to 15. My speedo doesn't really read until about 25 so its hard to say.

[ZanaEvyPapa]

tried the suggested startup procedure, but my glow plug light stayed on for about 2 minutes. I gave up waiting and just cranked it. It only went off after 30 secs of running. I guess my glowplugs are bad? Meh, I'll give this tidbit of info to my mechanic. Leaving for the shop now...
Thanks again everyone
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82 Diesel Westy
03 Jetta TDI
Gainesville, FL

[mwsnow]

[crazyvwvanman]

Good point. A careful read of the original post about the noise sounds like maybe the glow plug relay buzzing. The noise stops when the glow light goes out.

"Anyways, this light comes on at startup and coincidentally? turns off at the same exact time the loud grindy whiny noise shuts up. "

Mark

[Vanagonner]

That's what mine did when the glow plug relay failed- stayed on like that.
A new set of bosch duroterms and the matching relay is a happy combination.
I also installed a Ford starter relay ('80's bronco, I think- a firewall mounted thing) between the stock relay and the glow plugs. The wire that usually goes from the stock relay to the glow plugs now goes to the "trigger" terminal on the ford relay, and the hi-amp plugs get juice from the power terminal of the ford relay. It makes that dinky bosch relay last forever.
Good luck on the cooling thing-
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Sage
'82 Westy 1.6 D
the mighty n/a

[epowell]