The radiator shop called today and said that 2 out of 4 oil coolers were junk. My options are to try to replace the two junk ones with the same kind ( most dificult because I can't find any coolers like this that are threaded on the ends), OR use a different kind of cooler on one engine and use the two good ones on the other. The coolers I found that seem reasonably priced are the following.

A 16" x 3" from Revolution marine for $209.99 to my door or a Hardin Marine dual tandem oil cooler for $225.00 plus shipping Here are pictures of each

If anyone has any better suggestions or ideas please let me know

The Revolution cooler looks good to me. I don't get the idea of the dual cooler. Is one side for the engine and one side for the trans? It doesn't seem big enough either.

What size and hp engine/s? That makes a difference re: what size cooler you need. Also, you might wwant to check out Hardin Marine coolers. They're supposed to have baffles that move the oil around the inside the cooler for more exposure to the cooling water. TooOld can get them from Hardin, maybe a better price than CP.

I don't see the point in the double cooler either.

The double cooler is made by Hardin too. I think the reason behind the dual coolers is to increase the oil cooling capacity without increasing the length, plus they can take a ordinary 2" cooler and get twice the capacity out of it (the dual cooler) without going to a larger dia