Oil temp issue

type11969 · Post by **type11969** » Tue Jun 27, 2006 10:31 am

Jake-

Along with my valve clearance issue, I noticed on my drive the other day (90 humid degrees) that my oil temp was pushing past 220 while going 70-75. At 60-65, things would be okay (except for getting driven off the road). I'm running a mild 1.8 using Joe L.'s DTM, 30mm T1 pump, and Royal Purple 5W-30 oil. Oil pressure is never an issue, although at 220 degrees and idling, pressure did dip below the 10psi per 1000 rpm rule. I don't think I should need an additional oil cooler, but it seems like a small aux. cooler would keep the higher rpm oil temps down. What do you think?

-Chris

dstar · Post by **dstar** » Tue Jun 27, 2006 11:57 am

I think most of your oil doesn't get to go through the cooler!
It just gets dumped back into the case, from that 30mm pump.....

The factory used 26mm gears and the galleys are sized for that.
IF you want to INCREASE one thing on an engine, it affects other things.

My suggestion is to put a stronger spring in the pressure relief, or just
use a T1 piston, which is 1.5mm longer and will decrease the chance of
the oil getting *dumped* back into the case.

John, @ aircooled.net has gone over this in the SPeed and Drag forum recently, you may want to dig up that post.

John also sells a seat cutter that cuts the seat for the piston, as most of them are leaky from the factory.

Don

type11969 · Post by **type11969** » Tue Jun 27, 2006 12:38 pm

Yeah, I've actually been talking to John about that this morning, I was curious to get Jake/others input as well though. I certainly will try the longer piston or higher rate spring before going to the trouble of buying and plumbing a new cooler!

Thanks,

Chris

dstar · Post by **dstar** » Tue Jun 27, 2006 12:44 pm

For temporarily *trying it*, take out the screw and put a thick washer on it and screw it back in and see if it decreases the temp.

IT's a case of a little leaking long enough to take the tension out of the spring, then the springs lets MORE hot oil out and it gets weaker, and weaker and lets MORE hot oil flow over it and it gets weaker and weaker....and MORE oil gets let out.....

Don

type11969 · Post by **type11969** » Tue Jun 27, 2006 12:55 pm

There are two reliefs on the t4 case, correct? Which one should I be messing with?

How does leaking oil around the piston cause the spring to weaken? I guess I do fully understand how the pressure relief system works.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Jun 27, 2006 1:11 pm

215-220 is not hot.. Its on the upper end of the operating spectrum.

I wouldsay that the oil is too thin for one and for the second that the engine may not have optimum tuning.

What lower cylinder tins are you running?

As long as you have 40-45 PSI @ 3K RPM you are fine. More than 50 PSI at that temp aand RPM is robbing HP and is un necessary.

A 2056 with a DTM should never need an external cooler, I have ran one at 10:1 in 90+F heat in an early beetle and didn't need an external cooler.

Now, if your cam is dying you could be extrude honing the oil passages, ppump and bearings dropping the oil pressure. verify camshaft before going further.

type11969 · Post by **type11969** » Tue Jun 27, 2006 1:29 pm

I'm sorry, the oil temp was at 220 and was climbing.

I'm running std t1 lower tins.

This is only a 1.8 with a DTM, so I really don't think I need an ext. cooler, but temps certainly are climbing. It doesn't seem like my cam is going flat due to our conversation earlier today, but I'll pull a lifter or two to check it out.

-Chris

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Jun 27, 2006 1:37 pm

Pull the lifters from the intake of #2 and #4, they go flat more often than any others- FYI...

220 and climbing from a 1.8 sounds very odd. You should have a hard time getting to 200!
whats the gearing in the car?

type11969 · Post by **type11969** » Tue Jun 27, 2006 1:46 pm

Gearing . . . hmm, good question. I believe it is a SSC tranny from a superbeetle, but I bought it a while ago at a swap meet for 50 bucks and I don't remember the details. On 195/60/15s (ft) 205/60/15s (rear) it is turning about 3000 rpm at 60-65 stock speedo mph. By no means is she screaming when going 70-75. Thats why I'm a bit baffled by these temps.

Rough estimate using 205/60/15s, 60 mph, and 3000 rpm = a ratio of 3.67:1. Definitely some error in that though.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Jun 27, 2006 1:58 pm

I'd question tuning... try backing down the timing or richening up the carbs to see if it helps.

Do you have a CHT gauge???

Oil temp is NOT engine temp....

type11969 · Post by **type11969** » Tue Jun 27, 2006 2:09 pm

I forgot to add, I do have a cht, and temps never get above 325 degrees! I would think that with crappy tuning, I would be getting high chts. Granted, the cht is only on one head . . .

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Jun 27, 2006 2:58 pm

325 is actually a little high for such a small engine. when i tested an 1800 I found it hard to get it past 275 with a DTM..

I'd still pull some timing away and see what happens, but I'd also be running 20/50 oil in that engine. Royal purple 10/30 is very thin.

type11969 · Post by **type11969** » Tue Jun 27, 2006 7:00 pm

I'll definitely give 20w/50 a shot, but can you explain to me why the 20w/50 will reduce oil temps if I'm not having any pressure issues? Not that I am doubting you, I just want to know why this works.

Thanks,

Chris

udidwht · Post by **udidwht** » Tue Jun 27, 2006 7:11 pm

20/50 does a better job of carrying the heat away and to the oil cooler. 30 weight is thin as piss in an ACVW.

I also second, setting the timing back.

What type of oil temp gauge are you using?

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Tue Jun 27, 2006 7:16 pm

What I am about to write is only concerning the Royal Purple..

The 10/30 is very thin, be it hot or cold. The 20/50 R/P is about the same viscosity as a typical 10/30.

When I attempted to run the 10/30 R/P in my 912E I learned quickly that the clearances within the engine didn't like it as the pressure was very low and I also saw elevated temperatures.

Now, this is what I want to do...

Run the 20/50 and compare notes Vs the 10/30 and I'll tell you if the traits are the same. I only run 10/30 R/P in my 912E in very cold months, like December through January, but this year I didn't even change it, it's went 9 months on the current oil change.... I'm trying to kill it.