bertram31.com

just wondering, I may be able to get a pair pretty cheap out of a old 38ish bertram are they worth it, or no good for a 31
Thanks
Matt

wide and tall and capable of 550 hp. Too big for 2.. Maybe you convert to a single screw.

For----Get----It

No. To much iron

And even if they would fit, they are the worst motor DD ever built...take that back, second worst....the 8-92 is 25% worse.

UV

And I was annoyed I have to raise my boot stripe w 6btas

Prob be OK for a trawler, I would stay away.

Too big for a twin. Single would work, but you would get a bunch of grief...lol. They are very tall engines, unlike the CAT 3208's which are really low profile for 600+ cu inch engines.

I have to disagree with UV. The 6V92 got a bad rap right out of the box with cam problems in the first few delivered. This was corrected quickly and the engine went on to have a excellent service record.

The only real problem with the 6V92 is that it can be easliy turned up to stupid horsepower levels. Many were just turned up too high. Rated at 500 hp and below they will live a long time. At 552 cu inchs a 500hp 6V92 is producing less than 1hp per 1 cu inch. With Detroits this is the magic equation for a long service life, much above 1:1 and things can go south fast with the smallest overheat issue.

There were tens of thousands of them put in long haul trucks for years, good engine.

copy loud and clear, just checking
now, arent the 6v71 and 6v92 pretty mucvh the same size?
last year the brand x sold and she had 6v71s

The jug size is different ie 71 vs 92 still in a V. Never saw many up here in marine always the straight 6-71's in lieu of the 6V.

Still to big for a B-31 you can get the 53 series in though, maybe there's an old ruined Sea Ray floating around, they had used that engine in the 80's for some of their diesel boats.

JP's right, the 6V71 is a rare find in a boat.

The 71 & 92 designations identify the series and refer to the number of cu inchs per cylinder, but very few parts interchange between the series on Detroits. The older 2 cycle series being 53,71,92.

Lots of stuff interchanges within the series. 271, 371, 471, 671 all use the same piston, rods, liners, bearings, front and rear housings, etc. etc. 6V71 uses (2) 371 heads....Detroits were extremely modular in design.

Matt,

Ditto that which has been shared above. The 71 series was the workhorse line for GM, whereas the 92 series was an effort to juice up their line of engines to give more speed to the sportfishing fleet. I worked on a shrimpboat with a single 6-71 that we regularly "abused", but like a Timex it took a licking and kept on ticking. I also worked on a 43 Hatteras SF with a pair of 6-92s, and you can guess what happened.

Tommy

Lots of single 6-71's in workboats around here. Bulletproof and LOUD!!

I agree with you guys, the 71 inline series was best stuff Detroit ever put out. An inline 200-250hp 671N is the closest thing to a "forever engine" ever produced. They are still everywhere and well supported.

The engine going in my 25 Bertram project is based on 1/2 of the 450 hp inline 671TA. The inline "371TA" I am currently building will produce around 225hp and have all the good aspects of the 671TA in a much smaller package. Wish this boat was finished, it is spring and time to have a boat in the water!

The 53 series were great engines but they are no longer well supported anymore from a parts aspect. That's why I stayed away from building a 200+hp 453T (which would do well in a B25). The 71 series also has a stronger bottom end than the 53 series.

Ya i saw the 6v92s yesterday i dont know why i thought physically they were the same as 6v71s they are huge