6v71 model ID

[Wilky]

Folks
Can anyone tell me how to find out what year/model my 6v71 series motor is.
The info on the side of the rocker cover is missing. The motor is in our ex fishing trawler which we are converting to a full time live aboard.

I am pulling the motor down for a reco and will need the info to order parts. It is a non turbo fully marinised.

I am assuming it is either an LC or RC engine as the starter is on the left and oil cooler on the right, looking from the rear.
Any help will be greatly appreciated.

Cheers
Wilky

 

[jgmo]

Hi,

As far as LC RC, you are correct that the "arrangement" is C because the of the starter on the left and oil cooler on the right as viewed from the REAR of the engine.

L or R is simply engine rotation. If you are trying to determine engine rotation you can simply crank the engine with the starter and observe the direction of rotation from the FRONT of the engine. If the engine won't crank but is not seized, you can take off the air inlet and blower screen and observe which way the blower rotors turn while manually "rocking" the engine with a breaker bar. When the engine is rocked in the proper direction of rotation, the blower lobes will rotate "away" from each other or, in other words, toward the housing sides.

If the engine is locked up, you may need to remove the starter and observe it's rotation when energized. The engine flywheel will rotate in the opposite direction of the starter drive gear and, from that, you can deduce engine rotation.

The absence of the "option label" will make it necessary to "match" items such as injectors, emergency stops and other such items. But, being naturally aspirated, I doubt that there is much to cause you problems in the options category.

The model and serial numbers on later V-71 engines is stamped in the block on the upper right hand side (when viewed from the rear of the engine). The older engines had numbers stamped on the right side of the block toward the rear of the engine and are a bit harder to locate sometimes.

I hope this is what you needed, Good luck with your refit.
jimmyd

 

[Wilky]

Cheers Jimmyd, great info for me to go on with. Heap more questions but have a manual coming in the post and hopefully it will answer a few of them.

 

[jgmo]

Wilky and Diney

The info I relayed will be on or about page 7 in your coming shop manual. I'm not in the business anymore so I can't be of much help sourcing parts. Which, I think you will find will be the most difficult challenge of your endeavor. But, they're still out there and lots of places on the web selling cylinder kits and injectors.

The most important part of your "vow" is the "we". It works so much better than if it were "he";~)

 

[arboon]

6v71 model ID - odd number

Dear people
I am on a loss, so I hope for answers here. I have a Detroit Diesel, named Grey Marine 671. Looking at the block, it clearly is a 671, but the number stamped in the block does not agree with any of the serial/model numbers from the manual. My neighbor also has a GM 671, but its build is quite different. I add some pics and hope for recognition. I once heard that also models have been build in the Soviet republic. The last pic contains the number that is stamped on the location where usually the model/serial numbers are stamped, but it is different from what the manual tells me there should be. Any help is much appreciated. I need to replace my transmission, and without the proper info on engine type, I can't do much.
Best regards
Adrian Boon (from Amsterdam, The Netherlands)

 

[jgmo]

Hi Adrian,

You should start a new thread. This thread is almost a year old and you will attract more attention with a new thread.

Having said that, you should also write the numbers you have in your text with a description of their locations. While your pictures are ok, I can't make out the stamped numbers clearly. It sure LOOKS like a 6-71 but who knows? I'm not a Gray Marine expert and I don't know if these were produced anywhere else or not. But knowing GM Corporation like I do, it's hard for me to believe that they were cooperative in any "knock off" manufacturing.

However, MTU (currently a Rolls Royce subsidiary) has been using the GM and Detroit Diesel platform for decades to manufacture engines. I don't know if that may be what you have. I am not aware of any previous licensing agreements. I only know that they entered into a formal partnership in 1994 with Detroit Diesel.

Good luck.

 

[arboon]

Dear jgmo
Many thanks for your swift reply. I will start a new thread. I am in contact with MTU as well.
Thanks
Adrian.