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marine

  1. General Discussion
    I am thinking of switching from 15W40 petroleum based oil (Chevron) to synthetic oil....possibly Rotella T6, 5w40. Temps are typically 20F in the winter, up to 75F in the summer. Is this a reasonable oil for these motors? What are other folks using? Thanks in advance.
  2. General Discussion
    I just finished getting the 4b in my boat restarted after having sucked air from the fuel tank. This is the second time I've done it in recent years and am surprised at how long it takes to get it to fire after confirming fuel through the high pressure (HP) pump. After the first time sucking...
  3. General Discussion
    Has anyone else had problems with belts shredding on their 4b/4bts? The belt has not failed as yet and still looks "okay", but it is throwing off black dust and very, very small fragments. Inspecting the belt does not show clear damage (no torn off ribs, no nicks, no gouges). Currently I am at...
  4. General Discussion
    I won this at an auction last weekend, It originally had a pump attached to it. Total cost bid + auctioneer fee was around $1,400. Now I am looking for an adapter plate for a Borg-Warner Velvet Drive marine reduction gear. Any suggestions?
  5. General Discussion
    After getting air in the fuel lines do I need to bleed all four cylinders, or can I get a start with only bleeding three? Thanks for suffering this totally NOOB question.
  6. Performance Discussion
    I have 2ea cummins marine 4BTA 3.9 they dont go over 1800RPM neither of them . WHat can i do. I already replace the diesel filters, Oil filters, air filters, diesel lines, turbos seems working properly. I dont think its an injection problem because isnt smoking at all. ANyone that coul help it...
  7. General Discussion
    I am interested converting the Cummins ISF 3.8 into a marine engine. The ISF 3.8 is a 3.8 liter diesel engine made by Cummins in China which is widely available everywhere in the world BUT the USA. The brochure for the engine can be found by Googling 4951315.pdf If there is anybody who can...
  8. General Discussion
    Hey all- My local NAPA shop just sold me an 080537 belt for my 4b3.9-M (sn 44142600). The counted guy couldn't find it in his book, so he did a best visual match. Is this the right belt? Thanks.
  9. General Discussion
    Hey all- I've got a marinized 4BT3.9 that I'd like to drop into a boat that I'm working on. The motor has no air filter or filter housing. I'd like something as low as possible as the engine compartment is tight. What are my options? Thanks in advance.
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