Coolant leak around the turbo, S70 1998

[richardtexas]

Anyone else ever experienced this problem???

My 1998 S70 (turbo) no longer overheats, the temperature gauge does not register over the middle level until the low coolant light comes on. I replaced the radiator, upper/lower hoses, t'stat, and verified I do not have a blown head gasket. It idles fine for about 15 minutes, then while the temp gauge is still in the 'normal' level the overflow tank gets highly pressurized and gurgles with the (new) cap on. Shortly after that I see a stream of coolant spraying out of the back of the engine onto the turbo unit, which of course turns into a huge steam cloud.
I can't see that far below to determine where the leak is, but my supposition is that something in the turbo cooler area is leaking, the hot turbo is blowing pressure back into the overflow tank, and not allowing the coolant to circulate. I'm only guessing this since the overflow tank drains directly into the turbo cooling mechanism, and by the time there's enough coolant loss to prevent the coolant flow back into the tank it might be too late.
Any assistance or suggestions are appreciated! I've already sunk a lot of $ into this car and I need it to get to/from work!
Thanks in advance!

[Ozark Lee]

Chances are the problem is with the coolant line from the main coolant pipe to the turbo. If you trace the banjo bolt nearest the firewall back to the coolant distribution pipe it is the small coolant hose that goes between the line off of the turbo to the coolant pipe.

It is part number 9 in this diagram and it has part number 6842190.

Turbo Parts.pdf

(31.82 KiB) Downloaded 578 times

...Lee

[cn90]

1+,

From my reading of this topic, some people fix this hose (BTW use ONLY Volvo hose $15, no other brand!) from below but they get a shower of coolant in their face.

I came across another post that fix it by disconnecting the banjo connection. You need to re-cover the 2 washers if you want to re-use these washers (BTW I re-use washers all the time for 25 years). Otherwise, get new washers from dealer.


Here is the thread on removing the banjo connection:

http://volvoforums.com/forum/volvo-850- ... ine-63592/

...Its actually ez, just remove the 17mm banjo bolt that fastens the coolant line to the turbo, then reomve the lower clamp that fastens the hose to the coolant tube running to the expansion tank. I was lucky because I loosened the clamp, that was on there for seventeen years, with a 1/4 inch flex head rachet with a 7mm socket. I was actually able to turn the hex on the clamp toward me and then could get it off easily. I was prepared to cut it off with a dremmel tool if need be.

I have numerous write up about people trying to usfasten the middle clamp under the trubo. This a total waste of hours of time!!!! You dont need to remove the air box, downpipe etc; then try to reach the clamp hex with a 2 foot long screwdrive with a swivel head; like some dumb _ _ _es tell you.

Just unbolt the 17mm banjo bolt on the back and then take the whole thing off and replace the center clamp off the vehicle. It is virtually impossible to remove and install the center, firewall side, clamp if its in the car.

The hose is # 6842190, its 13.95 at the dealer. It's almost impossible to find a substitute generic hose because it has two different diameters.

Don't forget the two crush washers or seals that go with banjo bolt. They might leak if you reuse them and they are 50 cents at the dealer.

[richardtexas]

Thanks everyone! Seems like a pretty cheap fix, much better than a mechanic suggested, which was basically removing the entire turbo assembly and the associated labor costs!
I'll try this and post back with the results!

[jreed]

You probably have already seen the good write up by Tailor and others, but if not, it's worth reading for the parts diagrams and advice on tools and methods:

https://www.matthewsvolvosite.com/forums ... 2&start=15

[cn90]

Thanks jreed,

I have no leak but for $15, I will replace this hose in the Spring as preventive maintenance.
I will add some photos at that time.
Will try to do it from above as I hate taking a shower with coolant LOL.

[Ozark Lee]

Will try to do it from above as I hate taking a shower with coolant LOL.

Good luck with that one, It depends on how you find the hose clamp oriented where it comes off of the main distribution pipe. I had one where the screw head was faced inward, back towards the turbo, and two others where it faced outward. On the outward facing screw head there is a very tiny little space where you can sneak in around the heater line to get to it.

...Lee