dismantling heat exchangers Q

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vas

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my first take at heat exchanger cleaning and general messing about wasn't that bad but I'm stuck so need some pointers

Engines are IVECO AIFO, typical 4 exchangers all around.
gearbox oil one (the smallest) was easy to remove and undo the two caps. nice and generally clean, took 5mins to clean and reassemble with new o-rings.

Now, the compressed air exchanger is a massive thing, obviously cannot be removed as it's part of the cast alloy intake and has an blank cap on the one side and both pipes (in-out) on the other. I think that's fairly normal.
Problem is that I removed the one cap (with the two pipes) found some muck and bits of the red gasket silicone used to seal the old (and now dumped) raw water filters. Easily cleaned, fine.
heatexchanger_1.jpg


Problem is that the front cap that redirects the raw water back to the other side is not so easy to remove :(
Got good access but one allen screw is a pig. I'll have a go later on tonight and see what I manage.

That's an overview of the heat exchanger:
heatexchanger_2.jpg


Following pics show the endcap details:
heatexchanger_2a.jpg

heatexchanger_2b.jpg


So my Q is how the heck are you meant to remove the matrix with all the pipework out of there. The opened side has a lip over the alloy and the copper endcap bolts over it, fine.
The far (difficult to remove) side looks identical! Is the lip on that far side something that is removable (like a thick washer or something) and the matrix pulls off the other side? Do I need a mallet to carefully persuade it to pull out?
On the same lines, do I have any chance of removing the matrix with just the one endcap open? I guess the answer to this is NO.
Before you ask, unblocking the access to the endcap on the belts end of the engine doesn't look like an easy 5min job. Got to remove the coolant expansion tank which is a structural member supporting the alternator and various other bits. I have to admit i'm not familiar with truck engines but that's the first time I see such an arrangement...

I guess if I had the service manual I'd be able to solve my Qs but I only have the workshop manual. Engines are 8061SRM33.

cheers

V.
 
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Page 13 may give you some hints of assembly...

in my book that's a diagram not something helpful unless you receive the engine in a series of boxes and try to sort the puzzle. Unfortunately no serious hints are given on how to disassemble.
Studied this PDF before posting my Q, so yes, I can go about trying to fit my sockets, keys, spanners around trying my best to remove as little as possible of the ancillaries, but I'd have thought a service manual would have some clearcut recommendations on how to service the exchangers with everything in place...

Anyway, booked my afternoon/evening on the remaining 2.5 heat exchangers removal, hope I'm back home before midnight :p

cheers

V.
 
Looks like the end caps at front end will come off if you can get at the three/four nuts whilst it is still in position? if so then remove the Oring on the back end you have open and with a block of wood against the diameter of the matrix give it a tap with a club hammer (not too hard) the matrix should move towards the front then try to push it back in with a block of wood and lever, then repeat from the other end and eventually it will give in and come out. If this does not work then you have no alternative but to strip the whole lot down.

Another possible way is to rod the matrix and remove the forward water outlet pipe the grot will gather in the end cap then maybe you can flush it out with a hose or better a jet wash?

A better picture without the electric reel may help us! it looks like the back is held with that 90 degree bracket and the front by the air pipe but difficult to see in the picture.
 
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thanks omega2,

turned out much simpler that I thought...
took me 4 hours to remove the three heat exchangers (plus a couple of hours removing and dismantling the fourth a couple of days ago)
I recon 6h is not bad for a first time!

A slightly shortened allen was enough to undo the forward bolts, endcap off, the symmetrical copper flange was actually a washer to enable better sealing with two O-rings one on each side.
A mallet and a block of softwood and off it went (aft!)
On the port side of the engine I didn't have to remove a single thing in order to remove the oil and coolant exchangers.
Probably another tenner in O-rings and I should have them all back in place on Friday.
Need to refit the turbo (that was rebuilt) and the new exhaust risers. Weekend sorted!

Verdict: some crud on the first endcap after the impeller. All pipes are clean, some salt deposits on the endcaps easy to clean and doubt they'll be there after some hours of use anyway. Keep in mind I didn't flush the system when she was pulled on the hard three years ago!

One question I have now is what is the Vaseline like substance inside the thermostat housing (and why!)
Second question is what should I use to seal/protect the rubber to cast iron or alloy joints when refitting the lot.

cheers

V.

PS no time to update the main thread and post pics, so that'll be at the end of the week most likely
 
Cannot help with vaseline but just clean it out, could have been there for years, the end caps and rubbers get a coat of shaft grease (white grease) and looked at fairly regularly to see if they are leaking, a trace of salty deposit reveals the question, if so then off they come and get cleaned and resealed. If left they will rot either the case or the end cap.
 
Cannot help with vaseline but just clean it out, could have been there for years, the end caps and rubbers get a coat of shaft grease (white grease) and looked at fairly regularly to see if they are leaking, a trace of salty deposit reveals the question, if so then off they come and get cleaned and resealed. If left they will rot either the case or the end cap.

thanks,

more experienced guys around me in the yard when they saw what was in the coolant heat exchanger they simply pointed that it's formations due to the antifreeze in the coolant. Just need cleaning although I'd be interested what type of coolant antifreeze may produce less of that carp.
Update and continuing on the main rebuilt thread

cheers

V.
 
the end caps and rubbers get a coat of shaft grease (white grease) and looked at fairly regularly to see if they are leaking

couldn't find white grease, (tbh got some strange looks when I asked for it in two shops) so I'm using my nice deep blue marine grease, hope it's OK and the caps and rubbers wont mind the colour!

cheers

V.
 
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