Author Topic: intermittent low coolant (Read 4279 times)

vangirl · « **on:** October 18, 2006, 06:54:02 pm »

I have a 1991 Jetta TD. I bought it 6 months, in Nova Scotia (cold weather and salt country). I drove it across the country without any problems and then a few weeks after my arrival to Vancouver things started going awry:

1st: one of the belts broke for the alternator - replaced it
2nd: a low coolant light went on, no overheating - filled the tank, lite went off...
3rd: Temp gauge ran cold and warm, randomly

I replaced the thermostat to deal with variable temp readings but then I had another incident with low coolant lite going on, but the engine did not overheat. Added some more water...

I am trying to figure out if/where I have a leak - I was told I have evidence (deposits) of a leak with right flange - but it wasn't leaking for the past 6 months - could it just start leaking now?

I was also told that my water pump is "going" but it isn't making any loud noise so I shouldn't worry about.

What should I do? Should I take it for a compression test? I am low on funds and am trying to be low cost about it.

Anyone have any advice or know of a reliable, knowledgeable, affordable mechanic in the Vancouver area?

burn_your_money · « **Reply #1 on:** October 18, 2006, 07:00:35 pm »

Hopefully it isn't your headgasket going and eatting up your coolant.
Put a piece of cardboard under it when you park it and check for signs of leakage. Try and see where its leaking from based on where the drops are on the cardbaord.

I wouldn't worry about the WP unless it actually goes. It's a bit of a pain to do yourself, especially if you have AC. I got a new pump from canadian tire for $50 so if you DIY its not so bad. Again though, I wouldn't really worry about it.

vangirl · « **Reply #2 on:** October 18, 2006, 07:12:05 pm »

How could I tell if it is the head gasket? I know the tell tale sign is there being coolant in the oil but I don't have that issue. Are there other signs?

I've been meaning to put some cardboard to check for leaks...

Could the headgasket have warped when the belt riped? The engine did rise in temp when it broke but I pulled off the road right away. The engine was pretty hot though... Also, the belt ripped in August, and I only started having coolant issues mid October. Could there be a lag period for symptoms of warpage to surface?

burn_your_money · « **Reply #3 on:** October 18, 2006, 07:21:50 pm »

I doubt the belt breaking would damage the head gasket, unless the car was overheated.

Bad headgaskets can have lots of symtoms. I've personally had a bad headgasket dump oil into the coolant and vice versa, another one forced combustion gasses into the coolant, blowing the rad, and another one just leaked coolant out the front of the block.

A compression test will sometimes show a bad head gasket. With the car running do you notice excessive pressure in the coolant resevoir?

wolfsburgnut · « **Reply #4 on:** October 18, 2006, 07:29:01 pm »

That sounds like telltale headgasket signs to me. Check your exhaust when the car is running to see if a whitish smoke is coming from the tailpipe. As for the water pump, with the belt off check for play in the pump, and spin it over by hand. If you have any play or if the water pump doesn't spin easily its time for a WP. It sounds like something is giving problems in your accessories if the belts are breaking. I could be wrong but I think its pretty hard to warp a head especially if you pulled off right away b4 it got too hot.

Peter

wolfsburgnut · « **Reply #5 on:** October 18, 2006, 07:30:43 pm »

By the way when I had a bad head gasket it just started pumping coolant in the cylinders and puffing white smoke. Check you oil as well and see if it is milky and opaque. If it is, it is a head gasket.

Peter

vangirl · « **Reply #6 on:** October 18, 2006, 07:32:39 pm »

1) how would you define "excessive" pressure.
2) could the engine overheat between the time the belt breaks, temp rising and me pulling over? (it was maybe 1-2 minutes, max).
3) could head gasket problems start months after the warpage?

wolfsburgnut · « **Reply #7 on:** October 18, 2006, 07:41:01 pm »

How hot was hot? In the orange? Warning light flashing? If it was just up to 3/4 thats ok. As well head gaskets don't very often give alot of warning. With my car, one day it was fine, the next day it wasn't. Replaced the HG and everything was fine.

Peter

vangirl · « **Reply #8 on:** October 18, 2006, 08:05:49 pm »

How hot is hot you ask?
As I remember it, 1st the battery light went on, then shortly thereafter, the temp gauge was climbing (probably to 3/4+) and the light came on upon which I was like "What the #$*&^*, I have to pull over!!!" And I did... we opened the hood and found the broken belt, and the coolant was visibly chugging in the hoses after the car was turned off. The car was then towed away.

When you say there is no warning when a headgasket gives, do you mean there can be damage done and it could potentially withstand it for an indeterminant amount of time and then start to give? Or, one day it is fine, then overheating, then it is bad?

I guess what it all boils down to (pun intended) is that I am not sure if the car overheated or not, I just know that the temp was climbing rapidly and I pulled over.

wolfsburgnut · « **Reply #9 on:** October 18, 2006, 08:16:22 pm »

haha nice pun, I can't say for sure whether or not your head is warped and there was a lot of damage done, but my guess is that there wasn't, and as soon as you get the headgasket replaced and figure out why the belt keeps breaking, everything will be good again. Besides a good mechanic will be checking for all these things anyways. As for finding a good mechanic in the Vancouver region, send a PM to 935Racer, he is REALLY knowledgeable (and friendly) and lives in BC and has lots of VW parts for sale.

Peter

vangirl · « **Reply #10 on:** October 18, 2006, 08:24:38 pm »

This stuff is all new to me so I appreciate the explanations and contact info!

Another related question then: Is a headgasket replacement a big job? Labour/Parts?

I think I was confusing replacing the headgasket with a warped head! But now, as I read it, I realize they are different.

vangirl · « **Reply #11 on:** October 18, 2006, 08:38:16 pm »

Quote

It sounds like something is giving problems in your accessories if the belts are breaking.

what do you mean by accesories?
fyi i was told the water pump bearing is going and will need to be replaced.

LeeG · « **Reply #12 on:** October 18, 2006, 09:37:46 pm »

How fast is the coolant level dropping?

My car has used a bit of coolant for a while. Enough that the light will come on in a corner every couple months (~10,000km). So I have to top it up. I never see coolant in the oil and I never see oil in the coolant. On occasion I have seen a trickle down the block near the vacum pump, but it never persists. None of this is good news, but its been doing it for close to 100,000 km so I dont regard it as too ominous. YMMV

You dont want to run it with coolant in the oil, even if it seems OK afterwards, it is common to need bearings within a year of having the coolant leak fixed

Do you know what shape the belt was in before it broke? belts don't normally break, so it tends to indicate a problem with pulley alignment or something....unless the belt was ancient, or too loose.

vangirl · « **Reply #13 on:** October 18, 2006, 09:59:35 pm »

How fast is the coolant dropping you ask?

I don't have a clear answer cause the car went into the shop for a thermostat replacement and they added more coolant. But since then, the car was driven about 6-700kms and the light came on again.

I haven't seen coolant in the oil.

And I don't know what shape the belt was in, however, I was told by the mechanic who replaced the belt that the alignment, where the belt is? is off. They also told me that the new belt was put on a bit loose (but not too lose) to lengthen the life of the water pump.

burn_your_money · « **Reply #14 on:** October 19, 2006, 07:25:41 pm »

I drove on a blown headgasket for about 1000kms, and the previous owner probably put on 500 with the bad HG. Sometimes they die quick, sometimes they last a while. It's not good for your engine though to drive with a bad HG. One of my other failures only lasted 50kms, about a week of driving. I'd say chances are your head is not warped but it does sound like a bad headgasket.

To answer a few of your previous questions
1) how would you define "excessive" pressure.
Either blowing coolant out the cap (it's a pressure relief vavle) or bubbling when the engine is running.

Is a headgasket replacement a big job? Labour/Parts?

Yes it is. I'm in the process of doing it now actually. It does involve changing the timing belt, which when I looked into it to get it done (before I learned to do it) the cheapest I could find was $300 CAD, and that would have involved a 4 hour road trip. And that's just the beginning of the work. You need about $100 in parts.