Where to mount engine, tranny, p/s coolers
 

I ordered new engine, tranny, and p/s coolers and would like to see some good ideas of how and where to mount them for easy access and straightforward plumbing. I ordered a pair of 3"x12" core HD oil coolers for the engines, one has a 4" core p/s cooler added onto it,; and I ordered a pair of 2"x12" core oil coolers for the tranny's. I also ordered oil thermostats for the engine oil coolers.

I'm planning on dropping my new 540's in this weekend, so I need to decide where I'm gonna mount the coolers soon, especially if they'll be mounted under the engines. I'd prefer to not mount them under the engines though.

Here's what my bare engine compartment/bilge looks like.

Here's what I've got to deal with on the outer stringers...not much room. I'm leaning towads mounting the coolers behind the cylinder heads, above the tranny's.

Usually we mount the engine oil cooler right above the bell housing horizonally. We use 90 degree 1 1/4 brass fittings to pipe up the water. Hardin marine makes billet brackets to hold the cooler you will just make a bracket to mount the brackets and cooler to the block or bell housing. Then use aeroquip high performance fittings to pipe up the oil -10 or -12 sizes. Now if the motor has to come out again it wont make a oily mess taking everything apart and off the stringers.

Hi Monty,

I fabbed some brackets out of 3/16" plate stock and attached my coolers under my trannies. This was the most direct route for my raw water lines, and keeps them out of the way in the engine compartment. They were pretty easy to shape with a torch and a vise.

Keep in mind that oil coolers in general are heavy. They are not only a hefty piece of steel (or copper/bronze), they are also full of water and oil. So you'll need to mount them with something solid that will hold up to the rigors of an offshore pounding. This was my primary reason for choosing the trannies as a mounting location.

Nice work, so far!

Brian

Another pic

Other side

Original cooler (center) and beefier one. Also, before and after brackets.

Sanitary... very sanitary... good job!

Bell Housing Coolers
 

Are the coolers that are in bell housings large enough to cool an engine and a transmission? My boat had 3 external coolers for each engine and the builder removed all of them and replaced them with bell housing coolers. He said the coolers I had would not let the engines get warm enough. He did add a small power steering cooler.

Boat went from large blower motors to 540 NA motors if that makes a difference in the cooling requirements.

I still have the coolers, so I could put some/all of them back on if needed.

Thanks.

I picked up my coolers and misc hardware from Randy at Cobra Power. He tried to sell me bellhousings with coolers, but I went with the external ones strictly for money reasons. The bellhousing setup would have tripled my costs. IMHO, the bellhousing cooler solution is the cleanest one, but I have no experience with how well it cools.

Randy has been building big power for quite a while, and I have to believe he wouldn't try to sell me something that wasn't adequate.

How warm is "not warm enough?" My motors run 230-240 oil temps at WOT during a 45-min race. They are HP500 carb motors. Does your builder suspect you'll get cooler temps than these? Just curious, as my thinking is cooler is better with oil.

Good luck,
Brian

The bell housing coolers look neat... but have any of you guys seen how they work?... they are a wet plate type cooler... very efficient.... but... too easy to fill with crap.... the plates are thin and you can't get between them to clean... with the tube type ...they can be removed and cleaned out... can't do that with the plate type.

I was thinking the bell housing coolers would be a pain in the butt to get to. I have thru hull pickups, to a strainer, then the raw water pump then the bell housing coolers, then into the block. Maybe the strainers keep them from getting garbage on the fins. He seemed very sure I did not need the extra coolers and that the bell housing ones would work fine.

I'm running PSI supercharged 572 c.i. 1100 hp. motors in a 1984 38' Cigarette. I'm using a 1.5" water p.u. into my strainer and then into an Eikert 3 stage water pump.
I feed 1 stage of the pump directly to the bottom of one side of the factory dual-cooler bellhousing which exits on the top into an in-line P.S. cooler, then to the inlet of the block where the stock water pump would have been. Water exits the intake manifold, on that side, and dumps into the bottom of the headers, then out thru the tailpipes. I do the same with the 2nd stage of the pump to the other bellhousing cooler, etc. foreward. Both motors have an inline transmission cooler downstream from the outlet of the "stock" oil filter side bellhousing cooler.
The 3rd. stage feeds the innercooler. To make a short story-long, I'm using both factory bellhousing coolers to cool engine oil, in series, ( plumbed with a Mercury thermostatically controled oil filter ).
I have run this system for 3 seasons with absolutely no problems. The highest oil temp. that I've seen is 230 degrees on a 20 min. 4000-5000 rpm run.

Here's where mine are going. It's a work in progress. Copied from another OSOer. I want to have access to them. Using the two holes in the back of the heads and cast iron pipe clamps. Will line the coolers with foam strips at the clamps for shock absorption. PS/oil cooler is a ditto.

Dave

Thanks for the feedback guys. Alot of good ideas and recommendations. I think I'm going to mount the coolers behind the engines as well. I've got a TIG welder, metal cutting band saw, drill press, etc in my garage so fabbing something out of aluminum or stainless is no problem, I just need to figure out what I need to do. My engines are getting installed within the next week or so, so I need to figure it out soon. I bought the coolers and billet mounting brackets from Eddie Marine. I'll probably need to wait until the engines are in place to figure out how much room I've got to work with.