Cat C9 – Aftercoolers

[Allen Kandelman]

We recently put an offer on a 2008 42’ Riviera in South Texas (with a Seakeeper). Great boat, and well maintained (for the area). Flew out last weekend for survey(s) and happy to say thank both went quite well. I brought my own mechanic from home as I don’t trust most mechanics east of California

The boat is an 08. The engines are 07 with 2500 hours. It’s obvious the owner did MOST of his scheduled maintenance. I believe the engine is rated for 2500 RPM and we hit 2480. Coolant never got above 196 on the dash at WOT… and she ran comfortable 186-188 at cruising RPM 2150.

My question is this. The seller can’t seem to remember if he replaced the aftercoolers. This is obviously a big ticket item. He said he’s cleaned them. But never replaced the core. My mechanic is adamant they be replaced based on age. They have potential to leak salt water into the engine. I can’t find solid info on this anywhere else. So I am hoping someone here can confirm life expectancy of aftercoolers or CAT recommendations?

Thank you in advance!!

Topic

[BrisHamish]

I used to have a pair of (smaller) CAT c7s of about the same vintage. Similar to C9s in many ways, including the HEUI pumps and so forth.

For what it is worth, CAT recommendation (in Australia, at least) for replacement of the aftercooler cores on C7s was every 6 years. If you call a local CAT dealer, they will be able to look it up on a computer and confirm over the phone the lengthy of time for a C9.

If the seller had ever replaced the cores on the Riv you are looking at, he would remember very specifically, trust me! Those things are unforgettably expensive…

I reckon your mechanic is on the money. If that is an ‘08 splashed boat, then the cores are due for replacement by now, even if they aren’t leaking yet. Consequences of core failure, esp if in salt water, are BAD.

And yes, rated speed for a C9 is 2500 rpm.

Hamish.

[Author]

Replies