TheSamba.com :: View topic - Can aftermarket doghouse oil coolers be trusted?

Fri Jul 31, 2020 4:00 pm

I have more longblocks than oil coolers at this point and I wanna have at least one more cooler on hand.

Oil coolers in the classifieds look pretty beat. At least as beat as my spares with lots and lots of bent fins and who wants to straighten them out?

Most of the part sellers (CB Performance, Aircooled.net, etc.) sell non OEM stock doghouse coolers but are they any good? Can anybody vouch for them? Or against them?

Fri Jul 31, 2020 4:19 pm

ACN sells two different quality. I think cb sells the cheaper of the two. If cb uses them on their engines I dont see why they would be prone to failing. You could always spend the extra $100 on a NOS cooler :wink:

Fri Jul 31, 2020 5:21 pm

There are several companies that will clean oil coolers mostly for aircraft coolers but I bet they would do a VW cooler too, so if you could find a few used OEM coolers and have them cleaned and put them on the spares shelf.

eQ

Fri Jul 31, 2020 5:28 pm

RocketA wrote: At least as beat as my spares with lots and lots of bent fins and who wants to straighten them out?
It's much cheaper to straighten out the fins than to buy a new cooler you're unsure the quality of.

Fri Jul 31, 2020 5:31 pm

A used oil cooler that is loose is a crap shoot. But if yo remove it from an engine, you can inspect the oil and general condition. If the oil has no metal and the engine did not grenade itself, then have it boiled and pressure tested.

If you don't know the history, it could have metal shavings inside and might come loose after you reinstall it.

These are a crap shoot.

Fri Jul 31, 2020 6:01 pm

I had no luck finding a shop that dips radiators. More than one told me that the guys who did that all died of cancer years ago. My jbugs one has 4000 miles with no issues.

Fri Jul 31, 2020 6:10 pm

New oil coolers are very cheap compared to a catastrophic engine failure. I will never reuse an oil cooler from an unknown engine. I will never reuse an oil cooler that was on an engine that had a major failure. No matter how much you test and clean an oil cooler you never know what crap is inside that can become dislodged and ruin your new engine. New oil coolers are cheap.

Fri Jul 31, 2020 6:12 pm

FYI...

A friends shop installed a turnkey Scat engine for a customer. The installed it, tuned the carbs, took it for a road test and when the customer picked it up, he just got off the apron and oil was pouring out on the 3/4 side.

The rolled it back in and figured it was the flywheel or oil cooler seals.

The engine came out, the shroud came off and off came the cooler. The used a air nozzle to test the cooler and it was obvious that it split a seam.

The customer was not happy since he supplied the engine and had to pay for the repair. Not sure if he ever got any money back from Scat.

Fri Jul 31, 2020 6:52 pm

Since we’re talking air cooled opposed engine and aircraft I can say that neither Continental or Lycoming (the two dominant engine manufacturers in U.S.) do not clean oil coolers. They sell brand new engines and zero time remanufactured but absolutely install brand new coolers. Why? Because they could not come up with a way to guarantee 100% cleanliness, as stated above you might have some boogers inside that will come out into your new engine. It’s aircraft, it’s life or death no room for error.

So I should know better. For myself I don’t mind cleaning a used one but I’ve been lucky I guess. First I’d clean real well in parts washer then dry. Using a scribe carefully straightening any bent fins, Radiator shops call this a comb. reject any cooler that’s crushed, corroded or ballooned. Now I’d use something more aggressive like MEK to clean it again, you’d be surprised at how much baked looking shit comes out. Clean until it runs clear.

As for leaks they make a fixture to do pressure leak test. I’d proof Check and see if it holds 60 psi. Frankly I’ve been lucky no failures but it’s just my stuff for personal use. If it does shit the bed I’ll have nobody to blame but myself 😀

Fri Jul 31, 2020 7:19 pm

i tried dropping a pair of late model oil coolers into my ultrasonic cleaner. it helped, but i wasnt satisfied. the main issue it seems to me is that on the dog house style coolers, there is a little pocket at the bottom where crud can settle, and its almost imposible to remove because the area is larger than the inlet and exit holes. im wouldnt risk it on any engine unless its a run it till it blows up kind of thing. i know that you can cut the tops off of the early style coolers and weld em back on but i dont see how you could do that one a thin aluminum cooler like the ones being discussed.

Sat Aug 01, 2020 5:27 am

How do they clean the manufacturing crap out of the new ones before they sell them to you?

Sat Aug 01, 2020 5:52 am

Have had no issues with aftermarket oil coolers. I REALLY hate even reinstalling the original one if I am replacing seals, but do on occasion if it looks good, but we always clean them out first.

Sat Aug 01, 2020 9:52 am

The porsche guys know where to get the oil cleaner pressure tested. My dad had the one from his 912's done and it failed...

They put it through 2 tests

It passed the first
Failed the second

I dont think they even charged him since it failed.

I forget the name of this place, but could find it out.

Sat Aug 01, 2020 6:32 pm

I run them coolers in the hot jetwasher w/ a special adaptor -flush everything out. Rinse w/ fresh water, blow it out w/ high pressure air. It is as clean as you are gonna get.

I like factory parts -

Sun Aug 02, 2020 4:49 am

And no one checks the new ones for cleanliness? :shock:

That's trust!

Sun Aug 02, 2020 5:30 am

oprn wrote: And no one checks the new ones for cleanliness? :shock:

That's trust!
You'd be surprised.... try removing the top of a new 34PIOCT-3 carb and let me know how clean it is inside.

HINT.. they're not.

Sun Aug 02, 2020 5:39 am

Glenn wrote: oprn wrote: And no one checks the new ones for cleanliness? :shock:

That's trust!
You'd be surprised.... try removing the top of a new 34PIOCT-3 carb and let me know how clean it is inside.

HINT.. they're not.
Exactly! And how many times have people here been dressed down for not disassembling and cleaning their new piston and cylinders?

So - how do you guys clean your new oil coolers before you install them?

And further to that, how would that be different from cleaning the old used one? I am asking this because unless your old cooler is known to be full of very bad crap from a catastrophic engine failure there is no advantage in my mind to a new one. The cleaning process for a good used cooler would be no different than for a new one.

Sun Aug 02, 2020 5:47 am

oprn wrote: Exactly! And how many times have people here been dressed down for not disassembling and cleaning their new piston and cylinders?
Well... it's expected to clean p/c, but in the past You ASSumed a new carb was ready to go.

Mahle finally started to install the pistons upside down to force users to take them apart. They're only inside the cylinders for safe shipping.

BTW.. don't expect your Chinese distributor to be clean inside.

Sun Aug 02, 2020 7:09 am

I haven't done any doghouse coolers but have cleaned and pressure tested lot's of early coolers with success. I've used them on my own engines and sold a few with no issues.

https://www.thesamba.com/vw/classifieds/pix/4500446.jpg

Sun Aug 02, 2020 11:00 am

Cheap, easy pressure tester.