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Car just hit 100k, On a cold start i hear a squeal for like 30 seconds and it would go away. So I thought I was the pulleys so i in replace the Tensioner, 2 idler pulleys and belt, and while I was in there I also replace the PS seal it’s was leaking. Next day I did a cold start again I hear it again and on in 30sec. My question is how can you tell it’s the water pump is failing? And if you replace the WP do you have to bleed the coolant system or just fill and start the car with cap open and let the air out? Or do you do have to bleed it, how do you bleed the system?
Last edited by wease206; Mar 18, 2021 at 12:23 PM.
Start it with the belt off. This will eliminate everything belt driven. If the sound goes away, at least you know it's a belt driven thing. Next, use a squirt bottle to squirt water on a particular pulley as it's spinning. Most times, this will temporarily stop the squealing and tell you "who" the culprit is. A mechanics stethoscope or a long wooden dowel held to your ear (with the other end on/near various suspects) will help. The sound will be much more noticeable when you're near the bad guy.
My question is how can you tell it’s the water pump is failing? And if you replace the WP do you have to bleed the coolant system or just fill and start the car with cap open and let the air out? Or do you do have to bleed it, how do you bleed the system?
Bleeding the system can be tricky. I just did it (replaced thermostat) and found that idling with the reservoir cap off was not sufficient.
I thought I'd be clever and simply let it idle with the cap off, but there were weird expansion-contraction cycles that vomited $20/gallon coolant down the driveway. Not only did the system repeatedly swing between overflow and dry reservoir, I still had to top up the reservoir after two more hot-cold cycles. So to avoid wasting coolant down your driveway, I'd say fill while idling, then cap, then keep top up coolant when cold for the next cycles. This was what I did when I previously replaced the coolant and it was simple.
Make sure the sound you're hearing is not the secondary air pump cycling on and off. The water pump is located passenger side, under bank 1, toward the bottom, and should be pretty easy to stethoscope.
What's up with the Mityvac? Is that a vacuum line? In that picture are you vacuuming out motor oil also?
If OP doesn’t reply - that’s a topsider, or oil extractor.
About the only way I change oil on a GL with Off road skid plates on it these days.
I have one also. I can't imagine changing oil any other way.
This one looks funny, though - is that a vacuum line going in the top of the chamber? Mine has a pump, like a bicycle pump.
Of course, since I got to more than a quart per thousand miles, I don't change the oil at all anymore.
I'd really like to put a metal belly pan (the thing that covers the oil pan) and front guard (the thing that goes in front of the belly pan) on my GL. Went looking for the MB parts and got frustrated. You have source?
Last edited by eric_in_sd; Mar 19, 2021 at 05:20 PM.
Bleeding the system can be tricky. I just did it (replaced thermostat) and found that idling with the reservoir cap off was not sufficient.
I thought I'd be clever and simply let it idle with the cap off, but there were weird expansion-contraction cycles that vomited $20/gallon coolant down the driveway. Not only did the system repeatedly swing between overflow and dry reservoir, I still had to top up the reservoir after two more hot-cold cycles. So to avoid wasting coolant down your driveway, I'd say fill while idling, then cap, then keep top up coolant when cold for the next cycles. This was what I did when I previously replaced the coolant and it was simple.
Make sure the sound you're hearing is not the secondary air pump cycling on and off. The water pump is located passenger side, under bank 1, toward the bottom, and should be pretty easy to stethoscope.
What's up with the Mityvac? Is that a vacuum line? In that picture are you vacuuming out motor oil also?
I have two Mityvac this one hook up to a air compressor and just walk away hold up to 9.5qrts
my other is bike pump I hate to much work and standing around. Tomorrow I try the stethoscope.
BTW how does the secondary air suppose to sound like? I don’t think I never heard it or just don’t know it it sound.
I have two Mityvac this one hook up to a air compressor and just walk away hold up to 9.5qrts
my other is bike pump I hate to much work and standing around. Tomorrow I try the stethoscope.
BTW how does the secondary air suppose to sound like? I don’t think I never heard it or just don’t know it it sound.
The secondary air pump makes a high-pitched whirring noise that goes on and off when the motor is cold.
I'm curious how that Mityvac makes a vacuum with air pressure applied. Does it do some sort of venturi thing? Or the air pressure runs a vacuum pump? Curious.
I've been using the Mity Vac 7201 (with the bike pump) for about 12 years, now. I do boat winterizing on the side so it probably gets used, in addition to my cars, about a dozen+ times a year. I've actually been quite impressed with it as it typically only takes about 10 pumps - sometimes a second round of pumps - as long as the oil is warm. However, from also working in the industry, if I ever replace it, this is THE one: https://www.xylem.com/en-us/brands/J...k-oil-changer/ It connects to your battery (or battery remote post). Jabsco makes a slightly less expensive one, but this one works better and has a bronze head that is rebuildable. We have a couple of these at work and have been in service for a few decades.
FYI, whenever possible, attach your oil sucker's hose directly onto the dipstick tube, as opposed to shoving a small diameter tube down into the dipstick. Much faster oil sucking that way.
I've been using the Mity Vac 7201 (with the bike pump) for about 12 years, now. I do boat winterizing on the side so it probably gets used, in addition to my cars, about a dozen+ times a year. I've actually been quite impressed with it as it typically only takes about 10 pumps - sometimes a second round of pumps - as long as the oil is warm. However, from also working in the industry, if I ever replace it, this is THE one: https://www.xylem.com/en-us/brands/J...k-oil-changer/ It connects to your battery (or battery remote post). Jabsco makes a slightly less expensive one, but this one works better and has a bronze head that is rebuildable. We have a couple of these at work and have been in service for a few decades.
FYI, whenever possible, attach your oil sucker's hose directly onto the dipstick tube, as opposed to shoving a small diameter tube down into the dipstick. Much faster oil sucking that way.
If I recall correctly - like I said, haven't used mine in a long time - it had a 1/4" OD poly tube. Dos a larger OD fit all the way down the dipstick? 5/16" or 3/8"?
I'm flabbergasted that Mityvac uses a venturi to make the vacuum. I wonder what the cfm required is. That's a terrible way to draw a vacuum. I didn't check but I assume the Xylem product has an electric vacuum pump. Even a little diaphragm pump would work well - just set it and forget it.
Looking at OP's setup, I've also noticed others asking similar types of questions - it's flattering to have professional mechanics asking us, a bunch of amateurs, how to fix these things. I guess experience counts for something after all.
If I recall correctly - like I said, haven't used mine in a long time - it had a 1/4" OD poly tube. Dos a larger OD fit all the way down the dipstick? 5/16" or 3/8"?
I'm flabbergasted that Mityvac uses a venturi to make the vacuum. I wonder what the cfm required is. That's a terrible way to draw a vacuum. I didn't check but I assume the Xylem product has an electric vacuum pump. Even a little diaphragm pump would work well - just set it and forget it.
Looking at OP's setup, I've also noticed others asking similar types of questions - it's flattering to have professional mechanics asking us, a bunch of amateurs, how to fix these things. I guess experience counts for something after all.
It works pretty darn well. Extracted all the oil from my R500 in about 20 minutes. Just set and forget while I went and did something else, in my case raising the car to do a tire rotation. I'm just using an air compressor that you can buy at Home Depot or Harbor Freight. It runs maybe 25% of the time it is sucking.
FYI, whenever possible, attach your oil sucker's hose directly onto the dipstick tube, as opposed to shoving a small diameter tube down into the dipstick. Much faster oil sucking that way.
Oh wait - I didn't read carefully. You mean use the dipstick tube directly. Interesting idea, but if I were you I would try evacuating with a small tube after doing so. I'll bet a significant amount of oil remains in the pan, as the dipstick tube probably doesn't reach all the way to the bottom of the pan.
Or get a thin walled metal tube OD less than dipstick tube ID. Shouldn't be too hard to find, if speed is important enough. I found hot oil flows quickly enough I didn't mind the time.
Oh wait - I didn't read carefully. You mean use the dipstick tube directly. Interesting idea, but if I were you I would try evacuating with a small tube after doing so. I'll bet a significant amount of oil remains in the pan, as the dipstick tube probably doesn't reach all the way to the bottom of the pan.
Years ago, I installed a quick-drain fitting in lieu of the oil pan drain plug on the GL. Since I don't bother using the windage (skid) plate, all I have to do to drain the oil is to turn a little lever and walk away. So I've never sucked the oil out in the GL. My recommendation, though, was more "general" in nature. But, I have the done the exact experiment you mentioned on a number of vehicles and was only ever able to get out a few more ounces - which is completely and utterly insignificant. And when it comes to boats... I've probably changed the oil this way a hundred (literally) times.
Years ago, I installed a quick-drain fitting in lieu of the oil pan drain plug on the GL. Since I don't bother using the windage (skid) plate, all I have to do to drain the oil is to turn a little lever and walk away. So I've never sucked the oil out in the GL. My recommendation, though, was more "general" in nature. But, I have the done the exact experiment you mentioned on a number of vehicles and was only ever able to get out a few more ounces - which is completely and utterly insignificant. And when it comes to boats... I've probably changed the oil this way a hundred (literally) times.
Wow. Mad respect. Check out the big brain on Dennis.
Seriously, I'm impressed. Truth is, changing all the oil is overrated. Ideally, you would be continuously removing and replenishing oil - somewhat as I am doing with my leaky valve stem seal. So leaving some number of quarts behind in the pan is irrelevant. Only drain five quarts? Fine, just change the oil more often.
Do you ever worry about the shutoff valve getting knocked off the pan?
FYI, whenever possible, attach your oil sucker's hose directly onto the dipstick tube, as opposed to shoving a small diameter tube down into the dipstick. Much faster oil sucking that way.
whoa. Mind blown. I’ve done this with the little wheezer tube tens of times now, and thousands of pumps could have been saved?
Wow. Mad respect. Check out the big brain on Dennis.
Seriously, I'm impressed. Truth is, changing all the oil is overrated. Ideally, you would be continuously removing and replenishing oil - somewhat as I am doing with my leaky valve stem seal. So leaving some number of quarts behind in the pan is irrelevant. Only drain five quarts? Fine, just change the oil more often.
Do you ever worry about the shutoff valve getting knocked off the pan?
No, no worries - it's very small. Check out Fumoto oil drain valve. I've been using these on various vehicles for close to 20 years. But... Ha! I have to laugh at myself! I went out to take a quick picture for you guys and... the plastic windage tray was installed! I totally forgot that I just recently put it back on... because I was tired of seeing it laying against the wall in my garage!
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