Oil Temp. Seems rather high.

Hi Guys,

I have an '88 GTI Cab. and think that the oil temp may be a little high. It seems to hover around the 100c mark, rising to 105c after some enthusiastic driving.  

What makes me think that this is high is that I race a Lotus Motorsport Elise, and even during a race (where the engine is generally running between 6 and 9Krpm) the oil temp never rises above 95c MAX.

The Golf of course uses an oil to water cooling system whereas with the Lotus it's an oil to air cooler, but whether it's due to that I have no idea.

Before anyone asks, the (water) cooling system on the Golf seems to be fine - not experiencing any overheating, and the oil and filter are both fresh.

Am I worrying unnecessarily? what oil temp. should I expect to see?

Thanks.

My mk1 turbo diesel went up to 105 today after a thrashing  :twisted:
B ok
Bert

My GTI (admittedly, earlier and hatchback) uses an oil-to-air cooler, not a water one. Does this mean the (later) cabbys are different?

If I've had my foot down for a while mine goes up to about 104 and then settles back quite quickly after.

Normally runs at about 86- 90

I had the same 'problem' a while ago - try these thinsg out;

1. Is the oil temp this high without any electrical items on i.e. lights, rear window demister? The reason I ask is when I turn mt lights on, the display jumps about 15 degs, then when I switch lights off the temp display drops - think it's a dodgy earth for the MFA - the oil temp/water temp are fine.

2. This is what I think may be your problem. Give the car a good run, then get out and touch the pipes that lead to the oil cooler - one should be very HOT, the other not quite so as it takes the cooled oil back to engine. If neither pipe is HOT you have an oil cooler problem. Now, with mine that was down to the oil temp thermostat. I've put up a mail before on how to fix this - there's a pin that opens a valve to allow oil to head off to cooler when oil temp reaches about 110 degs. If this pin does not open, you will get problems of HOT oil.

PM me if you need more info - good luck.

 :wink:

just for info,
my 87 gti maxes at 105ish, normal driving shows 85/95 my rad thermoswitch rating is 85deg cut in.

paul c

 im confused, i thought all mk1s were watercooled, which was why the aircooled lot dont like us much :roll:

air cools the rad which cools the water which cools the oil, hence max oil temp of just over water boiling temp as the system is compressed.

how does the oil/air thing work on yours?

chz dave

The early and late cabbies do have different types of oil cooler (mine and Rach's are different) but as far as I'm aware they're both water cooled.

 :dontknow:

cabriaulait said

paul c

 im confused, i thought all mk1s were watercooled, which was why the aircooled lot dont like us much :roll:

air cools the rad which cools the water which cools the oil, hence max oil temp of just over water boiling temp as the system is compressed.

how does the oil/air thing work on yours?

chz dave

The oil cooler on my car has 2 oil pipes and a 'radiator' style flat face, and it bolts onto the front of the car next to the radiator. It doesn't have any water pipes into or out of it, so its an air-oil cooler. Some oil coolers are much more compact and have water pipes to-from them, so they are water cooled oil coolers.

yep i remember now, like this
http://cgi.ebay.co.uk/VW-GOLF-MK1-2-GTI-16v-TURBO-ETC-OIL-COOLER-KIT_W0QQitemZ320033720426QQihZ011QQcategoryZ9889QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

so it is a different system  hmmm
does it work any better, ive seen upgrades for them?

thanks

cabriaulait said

yep i remember now, like this
http://cgi.ebay.co.uk/VW-GOLF-MK1-2-GTI-16v-TURBO-ETC-OIL-COOLER-KIT_W0QQitemZ320033720426QQihZ011QQcategoryZ9889QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

so it is a different system  hmmm
does it work any better, ive seen upgrades for them?

thanks

I'd say generally its worse, although of course it depends on the size of the oil cooler and the (coolant) radiator. I'm figuring that the water-cooled oil cooler would actually warm up the oil quicker on startup, so it would bring the car up to temperature quicker. After that, its all down to the size of the radiator I guess.

The watercooled ones are generally considered more prone to failure. When they go you get oil in your water and there are stories of people changing healthy head gaskets before identifying the real cause. Not sure whether the aircooled ones work any better, think you have to run quite high temperatures for it to kick in.

Cheers

I have a 1985 Gti Cab.  The MSA reports the oil temp at a consistent 84 - 94 degrees normal cruising and I regularly see 104 when kicking on a little on the b roads - did max out at 130 once in July when I was caught on the M25 in a masive jam.

If your 88 Gti is running at 105 after a little bit of pushing i'd say you were right in the zone - exactly where you should be

Hope this helps.

M

bytor said

2. This is what I think may be your problem. Give the car a good run, then get out and touch the pipes that lead to the oil cooler - one should be very HOT, the other not quite so as it takes the cooled oil back to engine. If neither pipe is HOT you have an oil cooler problem. Now, with mine that was down to the oil temp thermostat. I've put up a mail before on how to fix this - there's a pin that opens a valve to allow oil to head off to cooler when oil temp reaches about 110 degs. If this pin does not open, you will get problems of HOT oil.

PM me if you need more info - good luck.

 :wink:

Thanks, I did see this posting that you mention - and it seems a worthwhile tip - however that is only for the earlier GTI's that had the air to oil cooler - the later models (mines an 88 Cab) have the water to oil cooler i.e. engine coolant returning from the (water) radiator is used to cool the oil - rather than using a seperate oil cooler rad!

So the general opinion appears to be that 105ish is perfectly acceptable - thanks for your all help guys.  Re the question about which is best - air to oil, or water to oil, i guess it depends on the conditions.  Of course whilst the vehicle is stationery the air to oil is doing nothing to cool the oil - it relies on airflow.  But if, as someone has suggested, there is a fault with the water to oil cooler then you could end up with oil in your engine coolant - depending upon the nature of the fault.

It seems that most new cars these days are fitted with water to oil coolers since the oil will be brought up to temperature quicker - but I think this is for the benefit of emissions rather than anything else - apparently more harmful emissions are produced on start up when the engine (and Cat. converter where applicable) are cold.  Bloody emission laws - that's why cars don't sound or are as responsive as they used to be.  

Get a load of this, I have a new Merc with one of those crappy paddle semi-auto boxes - on start up and in auto mode it will change gear at higher revs in order to get to the ideal operating temperature quicker - never mind that when cold the oil is like treacle and is yet to flow throughout the engine properly.  It makes me so mad!!!!!

I've seen my oil temp up to 130 ish before! 8O

I find an oil and filter change always brings the average oil temp back down again

Yup mine also averages 94-106, then fan kicks in at 110 bringing it back down to 94. These temps are after about 30-40 mins of motorway driving and sitting at lights.

yeah 105 on a water assisted oil cooler is about rite, they can only keep things as cool as the water in the engine! the air cooled ones seem to keep the oil a little cooler when the engine is pushed, from memory you can fit the aircooled one change the treaded tube in the centre from a water cooled one then use the water cooled and air cooled together, think one of the tuning companies offered this on there upgraded engines. i know we track dayed our 2.0l 8v and we had to watch how hard we pushed cause the temp rose to 138 on the MFA a friend was behind in his 2.0l mk1 and that was aircooled only saw 118 on our back bumper all the way round.

you can also change the radiator thermo switch to one that trips at a lower temperature.

Hairyarse said

I've seen my oil temp up to 130 ish before! 8O

I find an oil and filter change always brings the average oil temp back down again

Hairyarse your not supposed to wait for the oil to get that thick it won't go into the oil cooler before you change it! Lol 8O