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-   -   Why would a big B&B oil cooler simply not work? (http://forums.pelicanparts.com/showthread.php?t=487542)

Gogar 07-26-2009 07:26 AM

I'm still campaigning for a stethoscope or broom handle to the ear or something so you could verify the actual movement of oil through the lines, not just oil sitting around and getting hot through conduction as you mention. SmileWavy

175K911 07-26-2009 08:23 AM

My experience parallels what javadog suggested.....

Even though I only run the OE Carrera cooler, the results are the same. I had my car on the dyno last month, used an IR temp gauge to determine when the tstat opened up so we could do the pulls at full operating temp.

Before operating temp:
tstat housing- 170
feed line adjacent to the tsat- 160
feed line at the bottom rear of the front wheelwell- 140
return line at the bottom of the front wheelwell- 80
cooler and return line cool to the touch
feel line pretty darn warm but ok to grab

Once operating temp was reached:
tstat housing- 210
feed line adjacent to tstat- 210
feel line at bottom of front wheel well-210
cooler top tank- 200
return line back by the tsat-195
feed and return lines were too hot to grab, cooler was very hot.

After 4 pulls on the dyno:
tstat housing- 225
feed line adjacent to tstat- 225
feel line at bottom of front wheel well-220
cooler top tank- 220
return line back by the tsat- 200
feed and return lines were again too hot to grab.

So this tells me that even at an oil temp of 170, below the point the tstat is supposed to "open", the feed line was the same temp as the tstat housing. That sustains what I've always understood- the tstat doesn't direct oil to the feed line, it just opens to allow oil to return, thus creating the flow. And further, once the oil hit the 210 temp I could hear the oil flowing in the return line.

One other observation- when the oil feed line on my car was crushed just behind the front wheelwell, and crushed pretty badly so it was barely flowing, the line would be pretty hot up to the crush but the return line was cool. Yet tstat was opening and closing. I also understand that there's a pressure relief valve in the tstat that will just reroute the oil directly back to the engine if there's a restriction or blockage going to or from the cooler. My line was so crushed that once removed it barely allowed any water to dribble through. Yet the line to it was always hot. But anything beyond the blockage was cool or reasonably so. Could you have a blockage somewhere in the line from the tstat to the cooler? Or even a bad pressure relief spring in the tstat itself?

My caveat- yea, my oil temps are too high. I can easily see 240-250 on the track. Need a front cooler, but need a new job first before I invest any more $$$ in the mods to the car.

EmeraldE 08-24-2009 12:56 PM

B&B Center Mount Cooler
 
I also have a B&B center mount cooler and my car is a '78SC 3.0CIS. The cooler is the 5.5x2.25x20 version. It's plumbed in line with a 28-tube brass fender cooler. On normal and spirited street running it ranges from 195 to 210 in ambient temps currently of 90 to 95. However, on the track for 20 minute DE sessions I am hitting 240, after sustaining rpm in the 5-6,000 range for 5+ minutes or so. Both lines and coolers are very hot to the touch, either street or track, including both the driver and passenger ends of the B&B. I could hear the oil lines "burbling" at about 190 before I added the fender cooler, but it is not really audible now. I'll admit to not understanding the part about the T-stat opening partially, and being open to the front of the system at all times, so I have not checked the line from the T-stat back to the tank to see if it is lower temp?

The B&B is currently set up with -12 outlet/inlet fittings and lines, and I'm wondering if the combination of high RPM pressure and smaller line size is causing intermittent T-stat cut off so that I'm not getting full benefit of the cooler capacity. I am looking to upsize to 30mm lines to the B&B to run Elephant Racing lines throughout the system. Mine is currently plumbed top to bottom, but I'm thinking of trying to reverse that also.

It seems odd that FSW's cooler is not heating up throughout - mine is very hot at comparable temps even though it may not be flowing as well at high rpm.

Thanks,

Bob

78P930 08-24-2009 04:47 PM

Steve,
Quick question; Was your car doing the same thing before you put the cooler on?
Pat

Formerly Steve Wilkinson 08-24-2009 05:04 PM

Car was running fine with a 28-row Carrera cooler in the right front fender, though it got warm but not worriesomely so at DEs, I just thought I'd be a big-time operator and put in a big, cool-looking nose oil cooler, a dump chute to extract the air, and an IROC front bumper. Color me boy racer.

The weird thing is, for all my complaining, the car runs just fine. It hasn't been over 90 here in New York this summer, but I'll take it out and run it hard for half an hour--that's all I do, play with it occasionally, zero commuting, zero daily-driver stuff, never seen a traffic jam--and I'm damned if I can get the temp above 205-210.

I'm wondering if the reason the cooler feels cool is that my air-extractor chute, a big trough welded into the front of the car and through the front part of the trunk, is just so efficient that the cooler never heats up. I think a lot of people install these coolers butted up against the nose bulkhead of the car and maybe that's why they get hot: there's very little airflow through them, just airflow _against_ them.

As Iris Dement sang, "Let the mystery be."

Jeff Burger 08-24-2009 05:08 PM

What I'd love to hear is that other people who have big B&B coolers and run them hard enough to get 205-210 degrees of oil temp and then touch the cooler find that they're cold even though they're fully passing the oil.

I had a B+B front mount cooler with no fender cooler on my old 3.2 race car. I replaced the thermostat with a complete new factory one when I installed it . The temps rarely got over 200F . All parts including the cooler would be too hot to touch .

http://forums.pelicanparts.com/uploa...1251161684.jpg

DanielDudley 08-24-2009 05:46 PM

Steve, I have to believe that the man who told you to plumb the in line to the bottom of the cooler, and let the top fitting be the out flow was on to something. After all, you don't bleed brakes out the bottom.

On my SC, I am running up past 220 when caning it on hot days. If it rains, I get a consistent 180 on the gauge, and you can see steam rising from the trombone loop. I assume this means that my Tstat is working correctly to maintain 180 temps, but the trombone is incapable of dissipating enough heat unless wet.

My dubious two cents would be to plumb the radiator so that it is self bleeding, and then go out and get your car up to whatever temperature it thinks is hot. Then take a garden hose to the radiator while high idling in the driveway.

Mr Science is guessing that you should find that your temperature drops to 180 from the radiators new found ability to super cool the oil beyond the ability of normal airflow. If it doesn't, I would consider the Tstat to be suspect. If it does, then your radiator is merely working at it's normal level of efficiency, and nothing is wrong with the system.


Of course this advice is totally made up on the spot, and worth only what you paid for it.

Formerly Steve Wilkinson 08-24-2009 06:05 PM

Daniel, i did switch the fittings, makes no difference. Everybody from the engineer I contacted at B&B to Steve Weiner has told me it makes zero difference which is the inlet and which is the outlet, and I think I proved 'em right.

I replaced the thermostat innards about two years ago.

Jeff, do you have a dump chute behind the filter?

DanielDudley 08-24-2009 06:30 PM

Quote:

Originally Posted by Formerly Steve Wilkinson (Post 4855744)


I replaced the thermostat innards about two years ago.


?

I get what you are saying about the radiator. It is a devil's advocate line of reasoning, as is the comment about the Tstat. I would still want to test it.

Two years is a long time for a dog. I can't say for a Tstat, but I have seen watercooleds do some pretty weird things in short periods of time.

No doubt all is well. SmileWavy

EmeraldE 08-24-2009 06:48 PM

Size of feed line
 
Steve, trying to solve my problem of 240 degrees at DE sessions with the B&B, which I'm thinking may be related to either a) insufficient air flow, or b) my -12AN lines being too small and causing the T-stat pressure relief to divert oil flow from the cooler. What size are your supply/return lines to the B&B, -16AN? Have you had 10+ minutes of sustained 4,500-6,000 rpm and still not exceeded 210?

Thanks for the datapoint.

Bob

78P930 08-24-2009 06:57 PM

Steve,
It sounds as if it is working just fine.
Pat

Formerly Steve Wilkinson 08-24-2009 07:24 PM

Bob, yes, the fittings are -16AN. Hard to be exact about 10 minutes at 4,500/6,000, but five miles from where I live is a 15-mile-long, barely curved road through the West Point Military Reservation, essentially going from nowhere to nowhere. I do top-speed tests there on cars that I'm writing about, and that's where I run the 911: go like hell one way, turn around and do it again. Whether I'm at 4,500/6,000 the whole time I doubt, but I am doing 100, 120 comfortably (no traffic) and can't get the temp above 210.

Tinker 08-24-2009 11:13 PM

Bob,

I'd bet your problem is air flow and not the size of the lines / fittings. I had -12 routed to my front cooler and went to -16. Made no difference.

I tend to agree with FSW, from my understanding since the cooler is on the scavenger side of the system, it doesn't make a difference how the inlet / outlet lines are connected.

I wouldn't be concerned until temps start getting in the 230+ range.

Tinker

DaddyGlenn 08-25-2009 05:16 AM

Get thee to a track and run the piss out of it. Then check the temps.

Formerly Steve Wilkinson 08-25-2009 05:24 AM

Done that. Lime Rock, Watkins Glen. Cooler fins still don't get warm.

175K911 08-25-2009 05:58 AM

Gonna try to get mine on this week and will test at VIR next weekend. Just need to find the time.

euro911sc 08-25-2009 06:39 AM

Let me get this straight... you are complaining that your car runs great and the cooler does not get hot?? You actually have a problem with this? Half the guys I know would love to have this problem!

In all seriousness, you have tested the cooler... it flows. You have a new-ish t-stat so lets give that a thumbs up, unless you want to take it out and test it. Maybe you got one that opens at 230? Who knows. so throw those out of the list and all we have left are lines, engine cooler, engine t-stat, and pressure relief springs.

I think you can toss the engine oil cooler out of the list. Might be interesting to test the engine t-stat, but if the line to the front cooler is hot then I think that one is fine too.

that leaves lines and pressure relief springs... Would it be possible that at low pressure/low rpm the relief springs are working (closed) but at higer rpm they are prematurely opening allowing the oil to bypas the system? This would get hot oil moving toward the front, but when you get on it it would stop, thus the hot lines to the cooler and the cold cooler? Did you leave a rag in the pipe when you changed the cooler in/out last time?

If these check out ok just drive the car until you really have an issue that can help pinpoint a root cause... oh and have fun doing it ;)

-Michael

techman1 08-25-2009 07:27 AM

How easy would it be for you to remove the t-stat and place in hot water to check the opening? Not ever done this, but given the fact the t-stat was replaced 2 years ago, the lines should be easier to undo.

In addition to this, I thought an earlier poster said the engine t-stat/ cooler opens first, then the t-stat for the front loop. Are they in a series, so maybe the engine one is not opening all the way?

It sounds like flow is not the problem, but volume. A little flow would show the temps on the lines and cooler you describe.

aston@ultrasw.c 08-25-2009 02:09 PM

Quote:

Originally Posted by javadog (Post 4797998)
I'm not a fan of anything B&B makes. JR

Hmm...I was thinking of buying a cooler from them. What experience have you had? Maybe Setrab might be a better bet.

Formerly Steve Wilkinson 08-25-2009 02:25 PM

Michael, of course you're right, what am I complaining about? I just have this secret fear that I spent $1,000+ for nothing, but I'm figuring I've gotta be wrong.

Aston, in support of B&B--and it has nothing to do with the actual quality of their product, whatever that might be--their support is excellent. I e-mailed their sales department about my imaginary problem and promptly heard from an engineer who said to send it back, they'd cut it open and see if there was a problem. (It was unstated but assumed that if there was a problem they'd make it right, and that it had nothing to do with whatever the warranty period was, since I was a good year or two out of warranty.) Steve Weiner routinely installs B&B coolers in all the race and high-performance street cars that he builds. He tells me that he once had a brief problem with a short run of coolers that had the diverter plate mis-welded but that B&B quickly made it right.


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