75ZT Community

Those of us whom own a Diesel R75/MG ZT know that our O-rings can and do blow spit out etc, and lead to a slugish performance and blowing smoke also the black oily mess it leaves behind once the O-rings have been blown out etc.

So after seeing quite a few at the last nano meet i decided to take a good look at the intercooler (bend) outlet pipe stub as we know it consists of being held in by a bolt ajoined to the radiator and is pushed into the intercooler housing at the bottom of the radiator, the bend as two o-ring fitted to it which gives it the seal once pushed home, these can fail so i was wondering for added security and a better seal why not add a third below you will see my findings.

This first photo shows i have cleaned the intercooler bend and you can see the space for the O-ring which is last when pushed into the cooler, next is another section with four plastic bridges the center part and the we have the end of the pipe where the first ring would and should sit. Fig 1
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I thought if i was to cut out the centre plastic bridge x 4 round the pipe it would enable me to add another ring so i cut it out Fig 2
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When cutting i made sure i only cut to the depth of the O-ring and cut both sides of the bridge Fig 3
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Once i had cut all four to the depth needed i then cut out the nib of plastic left with a stanley knife held at an angle Fig 4
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When i had cut out all four i then used the edge of a file to smooth down any remains of the plastic bridge so the center looked identical to the first inset part of the intercooler pipe Fig 5
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The pipe is now ready to have the O-rings fitted as you can see i use an hook for this Fig 6
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First fit the last ring onto the bend making sure it is snug and only use Viton rings Fig 7
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Next fit the now new centre O-ring where the plastic bridges have been cut out Fig 8
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The next step is to fit the first O-ring which will be pushed into the intercooler and lies on a leadge inside the intercooler recess this is the first ring which as been known to swell and blow Fig 9
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The intercooler pipe is now ready to be fitted hopefully giving a better seal than with just two O-rings in place i have only modifed one these which needs to be tested yet, but i can not see why this should not work.
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Maybe even if need be leave out the first O-ring leaving only the center and last O-ring which then the pipe should push in a little further i yet have to make sure and will report back cheers Arctic.
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Good thinking Steve The progress of this mod should be interesting. VeeKay would benefit from it, I'm sure.

Arctic, another brilliant idea and I am sure it is going to work.

Roverite.

Another of those simple but excellent improvements ..from the master

Any updates on this mod , has it made things better. alot of people who run the remap have had more problems with seals , has anyone done this mod who runs a map?

1gp wrote:has anyone done this mod who runs a map?

Yes. Me

Russ did my 160 re-map some time ago.

Thanks to Steve I had this mod done on VeeKay at the Nano-meet. It makes a nice positive connection for the pipe. There was a lot of oil on my I/C pipe so will be watching that over the next few weeks but expect it to be eradicated now.

Hi Paul.
Yes please keep me informed and after about a couple of weeks it would be nice if i could get a torch down there and have a good look, as above i have heard about the 160 re-map and a bit of trouble with the seals, also Paul i will contact you about the other issue i am not to pleased about waiting on a delivery cheers Arctic.

As a follow on to the triple intercooler o-ring modification i have recently undertaken a chance to do an update on how to fit the O-rings with out removing the bumper here it is below,a relaxing Sunday morning 20 minute job cheers Arctic.

Intercooler O-ring Change Without Removing The Bumper.

Tools you will need 8mm socket and a long flat blade screwdriver, some gloves and some rag we are now ready to start.

First remove the engine cover 3 8mm bolts Fig 1-2
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Remove the cover and set it to one side safely with the bolts Fig 3
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Next remove the 8mm bolt holding the coolant header tank to the fan cowling and put the bolt with the engine cover bolts try and keep every thing in one place less chance of losing them Fig 4
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The next step is to loosen the jubilee clip attached to the EGR (Exhaust Gas Recirculation Valve) (CDT)Fig 5
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With the jubille clip loosened you now lower the coolant header tank down and to the left, it as to lugs/pegs which fit into a bracket so easy Fig 6
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The reason for lowering the header tank is it will give you more access to the 8mm bolt holding the intercooler bend to the side of the radiator shroud Fig 7
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You can now remove the bolt with the socket Fig 8
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You can now pull off the hose from the EGR which will need to be removed when you pull out the bend from the intercooler in the next process. Fig 9
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With the hose released from EGR reach down and pull the hose upwards removing the bend from the intercooler Fig 10-11
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With the hose and bend removed look down and you should see the stretched O-ring left behind Fig 12
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Fish this out sometimes both o-rings can be left behing if the other one as swollen too Fig 13
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With the O-rings removed clean out the recess in the intercooler wiping all oil traces away Fig 14
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Now you need to remove the hose from the plastic bend and clean it remove the old O-ring if still attached and replace with the new viton O-rings you have purchased.

Now wuth the new O-rings attached to the bend and smeared with a little vaseline offer the bend back to the intercooler hole Fig 15
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Make sure you hear alittle thud when the bend is pushed home and that the fixing point is lined up with the bolts hole on the side off the radiator shroud Fig 16
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Now you can copper grease the 8mm bolts thread and re-fit it securing the bend in place do not over tighten this bolts as yo can crack the plastci fixing point and it could snap later blowing the bend out of the intercooler believe me it can happen Fig 17
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You are now ready to fit the hose back on the bend and EGR first make sure you have turned the jubilee clip round so the slotted end is facing up as opposed to side ways when you took it off. Fig 18
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Push the hose onto the bend and the EGR and tighten the jubilee clip up Fig 19
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Now tighten up the jubilee clip attached to the bend now you can see the reasonfor turningthe clip round before, i so you can tighten it from above on the right hand side below the head light remove the rubber cover from the back off the head light if you need to for more access Fig 21
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Make sure it is tight Fig 22
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You can now re-fit the coolant header tank locating the pegs into the fixing holes Fig 23
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Fit the 8mm bolt again a little copper grease Fig 24
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Header tank back in place all the is left is to fit the engine cover Fig 25-26
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Job finished nice new tight viton O-rings Arctic

....WITHOUT taking the bumper off ! What am I going to do now on Sunday afternoons?

Another very useful How To Steve, keep up the good work !

Cheers

Mike

I did mine recently with vitton seals (no undertray, so front bumper off in 10 mins). On re-assembly, with the O rings correctly fitted, the elbow pipe wants to sit lower in the intercooler inlet than the mounting brackets will permit, so I compromised and lined up the mounting brackets. But a couple of days later I was having the same problem with oil drips and smoke, so off came the bumper again. There is obviously some flexing as the elbow pipe had worked itself out enough for the seal to leak. This time, put a hose clip on the intercooler inlet, and before tightening, put 2 cable ties inside it, 180 degrees apart looking from the top, facing vertically upwards with the zip locks at the bottom. Then I tightened up the hose clamp fully, taking care not to overtighten and fracture the plastic inlet tube. Similarly, I put a hose clip on the elbow pipe with the seals on. As there is a ridge on the elbow pipe, you don't need to tighten this clamp up fully, and indeed, you need to leave enough room for the cable ties. On lowering the elbow into the intercooler inlet, thread the upwards facing cable ties through the hose clamp on the elbow, then push them back down on themselves, over the outside of the hose clamp, and lock off in the zip lock - a small pair of thin nosed pliers helped. Once again, I compromised, as I wanted to use the mounting bolt for extra rigidity, and I fixed the elbow with the mounting bolt before pulling the cable ties as tight as they would go. So far it's all dry, but if it goes again, I'm going to cut the mounting eye on the elbow pipe, leaving a U shaped slot, so I can push the elbow fully down, and still get the mounting bolt through the mis-aligned eyes

Another approach which occurred to me, is to use a short piece of coolant/air hose (same dia as the one from the egr to the elbow, or maybe a slightly larger diameter reducing coupling) and use it as a bridging sleeve, secured with hose clamps, between the intercooler inlet tube and the elbow with the seals on, that way, the condition of the seals, or indeed whether they are present or not, will be irrelevant.

Pete something must not be in line as the securing bolt should be enough for the intercooler bend to stay in place mine as been in place for years now and not moved, also each year at the nano meets i check a few which were done the following year to see if they have came adrift, and if so ivestigate why, i would certainly not cut the support bracket.

You can always do as some other members have from another forum and put in a grub screw through the front of the intercooler socket and into the bend inside the intercooler by drilling a 3mm holes and using a self tapper.

I also have another idea in the pipe line please mind the pun,it as something to do with these below

Well, around 7,000 miles on, the mod I did seems to be holding up fine, so I'll leave it until it plays up. As you say, something must have moved (it's done over 170k), with the eye on the elbow lined up with the mounting bracket, it does not sit deep enough in the intercooler inlet and worked itself out ina matter of days.

What can occur is that the intercooler mounting lugs on the radiator could be broken. The 90 degree plastic intercooler pipe is then not correctly lined up with the intercooler hose.

Happened on mine, replaced the intercooler and all was OK.

Cheers

Mike