6CTA8.3 M2 420 Diamond Blowby test

[86Mekanic]

Greetings all, this is my 1st post here. I find this website very informative and interesting. I’m in process of purchasing a 94 Searay 440 Sundancer with 6CTA8.3M2 420HP Diamonds with approx 1750 hours. I’m trying to determine which items should be included in an engine evaluation/survey. Everything I’ve read seems to indicate a blow by test is critical in determining engine health.

Should this test be included? If so,when I look to Tony’s Tips section, I see there are no values on the chart for a 6CTA.
Does this mean its is not a valid test for this engine?
If it is a valid test, does the drawing in Tony’s Tips reflect the set up for a blow by test and what are the values required?

Thanks…

Topic

[86Mekanic]

I did find 2 pictures from the boats advertisement but I don’t think it’s possible to get much from them. However, to the trained eye there might be something there that pops out.

[86Mekanic]

Thank you for your info, there’s a lot there and I will look it over to try and draw out the needed info. I would love to take pictures for you but I cannot, I am in Dallas and the boat is in Sacramento. I will be visiting at the end of this month for a sea trial and engine evaluation. I’ll take pictures then, I want to make sure I get the info I need to make an educated decision on the powerplants condition and what the surveyor is doing for the money I’m paying him, right at a thousand.

So far his list has nothing more then a “look the engines over” list with no real tests other the no load rpm and wot rpm, oil analysis and coolant mixture test.

This surveyor was selected by the broker but after looking at his list, and studying here and at BD, I’m thinking of trying to find someone else. Possibly the Cummins folk in Sacramento, or,,,

If someone here might have a recommendation for a surveyor in the Delta area?

Thanks for taking time out Tony to answer my post, all your info and expertise is greatly appreciated

[Tony Athens]

Cummins–Measuring Blowby

Yes this is a valid test, but with that said, if you have the right guy on your boat and knows this engine, then IMO, it matters not as “the right guy” would know what is going on without a formal test.

As to doing it per the book:

Latest link:

https://quickserve.cummins.com/qs3/pubsys2/xml/en/procedures/100/100-014-010.html?q=blowby

Word copy below– Way too much for me to remove all the “un-needed fluff” right now.. Maybe down the road when I have some free time..

Why not spend a hour or so with a camera and lets “see” what things look like.. We are picture guys..

Tony

2 users thanked author for this post.

RiggersandFinsBda, 86Mekanic

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