Cat 3126

[Flick]

Reseached posts regarding the Cat 3126. Read to stay clear of the French blocks and that the 3126b are okay. Most of these posts were from 2004-05What about 3126 's manufactured in 2006? Were all 3126's "B's" by 2006?

[SeaEric]

The 3126 stigma is so bad, I would stay away from all of them. The buyers have heard the news and resale is very difficult. If the boat is priced so low that re-power is financially feasible, then maybe OK. But the boat would have to be a star in other respects. I wouldn't buy a a project boat with those engines in this market.

[Blaine Thorpe]

The 3126B is an electronic engine and did not suffer any of the same problems caused by the FAPS blocks on the 3126 Mechanical engines.

The 3126B is closer the the Cat C7 than the mechanical 3126 engines. I wouldn't be afraid to look at any of the 3126B vintages.

Blaine

[jim rosenthal]

I'd get a VERY thorough engine survey. The 3126 and 3116 were so bad that even if CAT made decent engines afterwards, they'd still have that name on them >^.^< You might try Boatdiesel.com forum for feedback on the 3126B engines. I don't know about C7s. They may be fine. I'd be hesitant to bet on it, though. I think CAT's reputation isn't good. They get OEM folks to put the engines in by floor-planning them and pricing the engines cheaper than the competition. Like a third versus MTU and MANs. Maybe that's what they have to do to sell their products- tilt the playing field.

One of our members who had a 36 convertible had 3126s- he went through at least two blocks and another crankshaft besides. This guy has run charter boats for decades, knows how to maintain his engines, and got 8000 hours on a Volvo diesel, for God's sakes. Now he knows how to do something else- change out engines. He got to do it several times. Talk about Velcro engine mounts.

I sold my 3116s and replaced them with 370Bs. No engine is perfect, but I got tired of waiting for the next thing to break.

[shark 1007]

i'd get a Cat guy to take a look, they have all the info on the bad blocks from a long time back. I bought a pair of 3116 350's to repower a boat and they're still going strong after 7 years or so. The guy that bought the boat is a no maintenance go fast type and they have fared well.

I have 3126 Mechanicals in the 41C and they are superb, 25 or 26 knots at 32gph total with a big tower, etc. My friend at Cat told me not to buy the electronic models.

I think the french blocks are easily identifiable and, with reasonable precautions, 3126's would make a decent choice.

Good luck.

[Bill Root]

I ahve a pair of factory OEM rebuilt 3126-300's in my 43' DCMY. They have been great: very fuel efficient, quiet and smooth. I have afriend who has them in his Ocean sport fish. he runs fast a lot and loves them. Just another opinion.

[jim rosenthal]

No question that there are some good engines out there, and there are some happy owners of them as well. My experience wasn't so good; I had a lot of injectors break and bent pushrods. One always ran a bit warm. And they smoked a lot- we could never get the proportion between the air flow and the rack opening exactly right, so the transom was always black. I always got home with them, but overall I wasn't comfortable. Always felt something was about to go wrong.

[shark 1007]

Jim

I understand your point well. I repowered, gas to diesel, a 1986 30 BlackWatch years ago. I had helped a Cat mechanic and he owed me a favor and sold me two rebuilt 3116's.

After getting her all set up, broken in and dialed in, my girlfriend and I departed for Ft Pierce to spend the night and then on to Old Bahama Bay. Upon servicing the motors the next morning, I found oil in the coolant and had to scrub the mission.

I was told a cylinder had elongated and the cure was to sleeve the block. He said it wasn't a big deal.

I didn't trust the motor after that, he sleeved them both, resold them and I bought new leftover 3116 350's from a dealer in Calif. for 12,500 each, my guy got money back to me upon the resale and all was well.

I spoke to nsider Cat folks who advised me what to look out for and the new power is perfect.

I too had the problem, learned from it and bought them again.