1995 E300 Diesel coolant flush, Airlift worth it?

[thatguy]

Hi everyone,

I'm getting ready to do some R&R on my cooling system, including new hoses, t-stat, coolant, and possibly radiator as it's original with about 200k. I just did the cap recently, so that'll stay, but I may change the expansion tank for good measure.

In any case, I remember last time I did the coolant flush I had a hell of a time getting the trapped air out of the system. My diesel Benzes have always been tough to remove trapped air from for whatever reason, but I never worried that much on the all-iron 617; however on my 606 I don't want any temporary hot spots due to air if at all possible.

Aside from running the car up to temp and removing the cap to bleed air, is there any other trick to purging it on the 606? Is the Airlift vacuum tool worth the price?

Is there a better way I'm not thinking of when it comes to the 606?

Thanks

[funola]

Originally Posted by thatguy

...............Is the Airlift vacuum tool worth the price?

Is there a better way I'm not thinking of when it comes to the 606?

Thanks

At $112 I don't think so. If you have a vacuum pump, you can fab something up for less than $20 that can do the same thing. 2 ball valves, some tubing, a rubber stopper. You are basically making a sucker tank, with the tank being your coolant system. You can get away w/o ball valves by using vise grips to pinch off the vinyl hoses, then the cost will be just the stopper and vinyl hoses if you have a vacuum pump already.

[thatguy]

I actually don't have a vacuum pump either, part of the reason I thought about the Airlift.

Is there a faster/better way to purge the annoying air from the system in these cars I've simply overlooked? Aside from getting it hot and running it endlessly with the cap off and heater on max. That always works fine in my other cars, but these diesel are stubborn.

Thanks

[mannys9130]

To drain the coolant, remove the lower rad hose and the block drain plug.

When refilling, pour the coolant into the upper radiator hose into the block. Once the block is full, put the hose back to the radiator, fill the expansion tank up the rest of the way, and squeeze the upper hose until you feel it's full of mostly coolant. Jack the front end up, start the car, let it heat up, and continue to massage the hoses until you get nice full, firm hoses. Rev the engine occasionally. Once you're confident, take it for a short drive, let it cool, top it off, done.

I wouldn't buy the airlift. A little bit of my time is worth it to keep a Benjamin in my pocket.

[thatguy]

Originally Posted by mannys9130

To drain the coolant, remove the lower rad hose and the block drain plug.

When refilling, pour the coolant into the upper radiator hose into the block. Once the block is full, put the hose back to the radiator, fill the expansion tank up the rest of the way, and squeeze the upper hose until you feel it's full of mostly coolant. Jack the front end up, start the car, let it heat up, and continue to massage the hoses until you get nice full, firm hoses. Rev the engine occasionally. Once you're confident, take it for a short drive, let it cool, top it off, done.

I wouldn't buy the airlift. A little bit of my time is worth it to keep a Benjamin in my pocket.

Thanks, I do remember filling through the upper hose last go-round, but it still seemed a bit more troublesome to remove the air from than any other cars I've owned. My 617 was similar.

I think that's what I'll do this time around, of course the fact that I won't be trying to get the car up to full temp with the heat blasting on a 25*F day will also help. I know those circumstances sometimes can make purging air a lot tougher...

[Zulfiqar]

draining filling a 606 engine is easy as pie.

drain the radiator and then drain the block - (easily reached from the passenger side)

flush it out if you wish, close off drains and fill engine from upper radiator hose "into" the engine - this way you get liquid at the "sense tail" of the thermostat completely. Then connect hose and fill up from the expansion tank slowly, start engine and let it run till the system reaches temperature - you will see a stream of small bubbles shoot from the thin air bleed line. Top off the expansion tank and you are 99% clear of bubbles.

The rest will bubble out themselves when you leave the car parked overnight.

[thatguy]

Thanks for the input guys.

I think this time around it'll be easier to purge the air simply due to doing the job in much warmer temps. I did a drain and fill of just the radiator recently to hold me over until the weather warmed up, so I"ll probably just do the same this time around (no flush as it's already pretty clean), but this time I will be refreshing a bunch of the old original parts that probably should be changed due to age and mileage.

[Steve_in_NV]

I have one and it works great, I've used it on all my cars. I also put in some "water wetter".

[thatguy]

Originally Posted by Steve_in_NV

I have one and it works great, I've used it on all my cars. I also put in some "water wetter".

I've read of people using Water Wetter before, never tried it myself. I found even with the A/c running on 95*F+ days and pulling hills, the hottest I get is around 100*C, never seen it go above that next line up.


Using an Airlift on my other rigs was another reason I had considered it, but they all seem to be really easy to bleed the old fashioned way. I do have one of those bleeder funnels that attaches to the radiator directly of my Toyotas, but I don't see it working on the Benz unfortunately.

[Zulfiqar]

Originally Posted by thatguy

I've read of people using Water Wetter before, never tried it myself. I found even with the A/c running on 95*F+ days and pulling hills, the hottest I get is around 100*C, never seen it go above that next line up.


Using an Airlift on my other rigs was another reason I had considered it, but they all seem to be really easy to bleed the old fashioned way. I do have one of those bleeder funnels that attaches to the radiator directly of my Toyotas, but I don't see it working on the Benz unfortunately.

The concept behind the bleeder funnel is to raise the level of liquid so it can push itself in and eventually displace out air.

to achieve this in an OM60x engine you fill the engine from the top radiator pipe into the engine and then into the radiator and button it up. The airlift is a good tool for some cars e.g. the toyota MR2.

[babymog]

Water Wetter works great for keeping the heater core hotter, engine cooler, ... will boil your windshield-washer tank dry though (if yours is heated) with the extra heat.

There is a Diesel Water Wetter also, which is harder to find and more concentrated.

It does not however help with bubbles.

[mannys9130]

Just beware of cooling system additives in regards to the G05 that we use. The Royal Purple additive caused QUITE a mess for this guy.
Royal Purple Purple Ice Coolant Additive Woes... - Mercedes-Benz Forum

In general, I don't like using additives in anything except fuel (for valid reasons like antigel and cetane boost).

If you find that you have cooling system problems, a degreasing and a good citric acid flushing is what you should try first.

[babymog]

I agree with Manny that you need to start with a clean cooling system in good condition. Putting additives in before ensuring proper condition is not going to be a long-term solution.

However, the RL Water Wetter is compatible with the HOAT (G05), and does enhance heat transfer. Some cars in some environments (ex: my W140 diesel) just don't have the cooling capacity for extended climbs etc. (owner's manual specifies techniques to avoid overheat in such situations) and a little assistance is justifiable.

[EDBSO]

I have used water wetter in G-05 without problem, even in Death Valley at 121F

[mannys9130]

Good to hear Water Wetter doesn't cause problems with our G05.

Also altering the mixture of water to coolant will provide slight increases in cooling or freeze protection depending on the season and mix you choose. More water makes for better cooling, more EG makes for better freeze protection.