Oil on Intake side of Turbo

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bobhatton
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Re: Oil on Intake side of Turbo

Post by bobhatton »

Do not use a shroud on an intercooler or rad, it blocks off the air flow when you need it most.
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MartinF
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Re: Oil on Intake side of Turbo

Post by MartinF »

bobhatton wrote:Do not use a shroud on an intercooler or rad, it blocks off the air flow when you need it most.


I think you mean a badly designed cover, rather than a proper well designed shroud. :)
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bobhatton
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Re: Oil on Intake side of Turbo

Post by bobhatton »

MartinF wrote:
bobhatton wrote:Do not use a shroud on an intercooler or rad, it blocks off the air flow when you need it most.


I think you mean a badly designed cover, rather than a proper well designed shroud. :)


No, any shroud. They are not needed, the fan will pull all the air needed when the car is at a stand still, then when the car is moving forward there is all the airflow to do the real cooling, the shroud and fan is then blocking off the air flow.
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Pauln
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Re: Oil on Intake side of Turbo

Post by Pauln »

mr299ron wrote:
Regarding the "unbranded intercooler" you have fitted to your mr2 - Do you have/have you had any issues with cooling? I would like an intercooler soon but can't find any reputable ones for a good price. Could you do me a massive favour and search "Intercooler Kit Complete MR2 SW20 Turbo Greddy HKS Apexi" on eBay and you will see the used intercooler kit I am interested in buying.

It already has the fan/shroud and is only £125 but I would like to know if these GReddy knockoffs are any good. And since you've mentioned you have one; have you replaced it because it's xxxx, or has it generally been okay?

Cheers
99ron


That looks to be pretty similar to the setup fitted on my car. It seems to be generally accepted that these don't work as well as the "real thing", but providing it's a decent copy it still ought to be an improvement over the stock IC.

There have been a few posts about the welds on the brackets giving way possibly due to vibration passed from the engine to the IC via the pipework. I took Peter's advice with the connection to the hot pipe and replaced the initial right angle ali pipe with a silicone one to add a bit more flexibility and used silicone hump connectors where the metal pipes connect to the IC to again add a bit of flexibility and isolation from any engine vibration transmitted.

The block off shroud (flat plate in that ad) should be fitted between the body of the car and the IC core to try to make sure that all the air coming through the engine bay side vent is forced to pass through the IC and not allowed to pass around it.

Originally my IC simply used the stock fan without any form of shroud. When I fitted a SPAL fan I also fitted the shroud that GTS Chris supplied. This is claimed to ensure that the fan draws air through the whole IC core not just the section immediately under the fan, hence the stand off on the shroud.

The counter argument, as has been stated, is that the shroud actually restricts natural airflow when the car is on the move.

I'm afraid I've never run the sort of tests needed to establish which approach is best overall, so can't comment one way or another.

All I can say is that I'm happy with the setup on my car, and the IC core always seems to be nice and cool when I've stopped to check.

But I'm afraid I don't have a temperature probe fitted so don't know how effective it actually is at reducing the temperature of the air in the intake.

Certainly fitting the Greddy cold pipe, rather than the pipe usually supplied with these copy kits has improved the clearance between the hot and cold pipe. Previously these two pipes actually touched at one point. So that ought to help reduce radiated heat transfer between the two. I have wondered a few times about wrapping the cold pipe, but again there seem to be differing views about whether this actually makes a difference.

The bit I've never really understood is why the stock throttle body is then "heated" by including it in the engine coolant system. I can only think that this to do with running these cars in colder climates, as I can remember sometimes having carburetor icing problems with with my old Triumph bonnie in really cold weather.

Paul
mr299ron
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Re: Oil on Intake side of Turbo

Post by mr299ron »

As far as I'm aware the fan extracts air from the intercooler and the airflow comes from the side vents. All adding a fan shroud on the intercooler will do is slightly restrict the air flow being passed through the IC, however it's nothing I would worry about, as the air is still being extracted at the end of the day.

My fan will always been running too, as I will be wiring it the same as the stock IC fan, so the airflow should always be flowing, meaning I shouldn't see any issues.

As Paul has just backed up, I'm sure there hasn't been any tests, just opinions on what to run. Similar to bunging up the PCV intake hole on the intake pipe. You probably shouldn't do it, but it doesn't mean you can't do it.

At this point £125 for the intercooler and fan shroud kit is a pretty reasonable price so I'd be silly not to go for it!

Cheers
99ron
jimGTS
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Re: Oil on Intake side of Turbo

Post by jimGTS »

vent the pcv gases if you can.

long as you block the hole in the intake it shouldnt cause any AFM issues AFAIK

in terms of the shroud, i hovered a fan over my old phoenix's power intercooler, still did the trick im sure.

no way to measure it really though.


low speeds, or parked up with no shroud, that downpipe will radiate a ton of heat onto the core and heatsoak it. with a shroud in place, i would have to guess this wouldnt happen as much as its being "protected" by the shroud??

so there are pros and cons to the shroud really IMO.
2mad
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Re: Oil on Intake side of Turbo

Post by 2mad »

mr299ron wrote:As far as I'm aware the fan extracts air from the intercooler and the airflow comes from the side vents. All adding a fan shroud on the intercooler will do is slightly restrict the air flow being passed through the IC, however it's nothing I would worry about, as the air is still being extracted at the end of the day.

My fan will always been running too, as I will be wiring it the same as the stock IC fan, so the airflow should always be flowing, meaning I shouldn't see any issues.

As Paul has just backed up, I'm sure there hasn't been any tests, just opinions on what to run. Similar to bunging up the PCV intake hole on the intake pipe. You probably shouldn't do it, but it doesn't mean you can't do it.

At this point £125 for the intercooler and fan shroud kit is a pretty reasonable price so I'd be silly not to go for it!

Cheers
99ron



I ran an ebay intercooler (xs power) plus a fan on a swich in the cab , ran it most the time .. no shroud .

As for oil in the intake , ive had many turbos do this with the pcv vented to atmosphere .. as long as its just a light mist build up .. thats taken months to accumulate i wouldnt worry to much 8-[ .. if its so bad you need to empty your intercooler of oil every month then yes your compressor oil seals have failed ](*,)
mr299ron
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Re: Oil on Intake side of Turbo

Post by mr299ron »

All looks good in terms of the turbo's health so far. No play, just an oily film, no puddles of black stuff. I imagine the intake piping had never been cleaned, so it could be from 20 years of running! ha!

I will inspect the stock IC once I fit a new one in the coming weeks. I imagine all is okay, but you never know at this point.

Going back to the fan shroud; yes, installing a heatshield/shroud on the IC would seem to defend heat from the downpipe, as Jim has said, so I think this would be a good idea nonetheless. You could of course heat wrap the downpipe, but that seems a lot more effort than just installing shroud on an intercooler :P

Should I keep the PCV from venting to atmosphere for ever, or install a catch can? I can't justify spending £145 for the proper 19mm fittings catch can at the moment if I can just vent the gasses to the atmosphere. However, the pipe is still in the engine bay, so I may buy some silicone pipes and route the pipe down and under the car and then cable tie it to something rigid so it properly vents to atmosphere..

Cheers
99ron
jimGTS
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Re: Oil on Intake side of Turbo

Post by jimGTS »

you can build a baffle catchcan for much less than 145.

just get an ebay one that isnt sealed, ie you can open it up.
build a crude baffle system, i got some thin sheet metal, cut lots of holes in it and folded it inside.
lots of surface area to catch that oily mist.
find some bigger fittings, drill and tap for the fittings. job done, £20-30 catchcan 95% as good as a baffled one for 5 times the price.


it is worth noting, that yes you want the fittings large, but on the rev3+ intake pipe, there is a huge restrictor in the rubber nipple part of the pipe, it goes down to like 5-10mm.
which is way smaller than the oem catchcan! so you could have as large fittings as can be, but that restriction needs drilling out to make it work!

on a rev1/2, there may well be the same issue, worth looking into.

but if you are going to vent to atmos, maybe just a simple cheap non baffled can is fine, or no can, just a hose and breather filter.
mr299ron
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Re: Oil on Intake side of Turbo

Post by mr299ron »

I'm more of a bolt on kind of guy, but I will have a little look into that idea.

But, isn't that why I need 19mm input/output fittings, because the PCV hole on the intake is 19mm? Whatever size this hole is, is what size catch can I will pick up. The Rev2 might be different.

Well, as long as a breather filter doesn't damage anything, I can't see any reason why not?

Cheers
99ron
2mad
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Re: Oil on Intake side of Turbo

Post by 2mad »

mr299ron wrote: No play, just an oily film, no puddles of black stuff. I imagine the intake piping had never been cleaned, so it could be from 20 years of running! ha!



Sounds sound to me .. 20 years of oil residue .. just keep an eye after fitting oil breather or catch can .. only worry when theres puddles of oil in the intake :thumleft: even then its not the end of the world , ct26/ct20b's are strong turbos :)
jimGTS
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Re: Oil on Intake side of Turbo

Post by jimGTS »

mr299ron wrote:I'm more of a bolt on kind of guy, but I will have a little look into that idea.

But, isn't that why I need 19mm input/output fittings, because the PCV hole on the intake is 19mm? Whatever size this hole is, is what size catch can I will pick up. The Rev2 might be different.

Well, as long as a breather filter doesn't damage anything, I can't see any reason why not?

Cheers
99ron



my point is the hole in the actual intake pipe is small on a rev3+. so shouldnt matter a huge amount.
yes on the outside it looks large, but inside was restricted.

it maybe the case thats similar on a rev1/2 pipe also. youd need to check.
MartinF
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Re: Oil on Intake side of Turbo

Post by MartinF »

bobhatton wrote:

No, any shroud. They are not needed, the fan will pull all the air needed when the car is at a stand still, then when the car is moving forward there is all the airflow to do the real cooling, the shroud and fan is then blocking off the air flow.


I guess all those car manufacturers got it wrong then and they should just let the incoming air escape round the side of their radiators and intercoolers :-k
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