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Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 14299
Experience:  Degree in Marine Technology. Gas and diesel marine mechanic.
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I started engine and it made a noise like bracking metal and

Customer Question

Hi there/ I started engine and it made a noise like bracking metal and stoped. turn it over again fine, but was making a knock. compression fine in all cylinders, but when tester is on no 6 cyl. it make this knock
Submitted: 1 year ago.
Category: Boat
Customer: replied 1 year ago.
when i put spark plug to no 1 or number 6 cylinders only, it makes this knock. without plugs no knock, turns freely
Expert:  Jason replied 1 year ago.

Hello my name is ***** ***** am I speaking with?

I just want to make sure I understand you correctly. If you disconnect the spark plug wires on #1 or #6 the knocking noise goes away. Is that correct?

Customer: replied 1 year ago.
not spark wires. Sparks itselfs. i removed all the sparks. engine is not running, but turns over for test reasons. making knocks only when put spark to no1 or no6 cylinders. Means this cylinders under pressure
Customer: replied 1 year ago.
I mean spark plugs. Sorry
Expert:  Jason replied 1 year ago.

Will the engine actually run?

What did you get for compression numbers?

Lastly, what is the story on this engine?

Customer: replied 1 year ago.
all the story above. engine ran. Compression 160 in all.
Expert:  Jason replied 1 year ago.

Are you near the engine now to run it by chance?

Customer: replied 1 year ago.
but I do not want to run it. Knock is obvious from no6 or no1 cylinders
Expert:  Jason replied 1 year ago.

I think the damage is already done here. What it sounds like is you have either rod knock or piston slap. Rod knock is caused by bad lower connecting rod bearings. Piston slap is caused is caused by a poor fit between the piston and piston pin, at the top side of the connecting rod. Both sound similar. The test for this without stripping the engine down would be to run the engine, and disconnect the spark plug leads for those 2 cylinders. If the noise goes away, it's rod knock. If it quiets down somewhat but is still there a little bit, that would be piston slap. Does that make sense?

Customer: replied 1 year ago.
no. it knoks without engine running. What is the point to run engine if it knocks without running
Expert:  Jason replied 1 year ago.

If it's knocking without the engine running it has internal damage, and is going to have to come apart and be inspected. But again it would be either connecting rod knock or piston slap. Do you have any further questions on the issue?

Expert:  Jason replied 1 year ago.

Was there anything else?

Expert:  Jason replied 1 year ago.

I think that should do it. But I do want to make sure you are happy with my service before you go. If you had a further question on the issue by all means feel free to ask. If not, Just in case you do not understand the way the website works (and some folks do not). You do have to put forth a positive rating in order for it to credit me for helping you. When ratings are not done, the website simply keeps your deposit and they will not credit me. The ratings box is located at the top of the screen. To rate, you must select the star you wish and also confirm it. Please let me know if you run into any problems or errors when trying to do it. If you do have a problem, or if you can not see the ratings box which is at the top of the screen. Please reply back "I rate Jason's service _______" and fill in the blank.

Questions do not close out, so if you have to come back later on with follow up questions to the issue you still can even after doing a rating.

Thank you
Jason

Expert:  Jason replied 1 year ago.

Hello, I noticed no rating has been put through. The website has charged you but they will not credit me for helping you out until that rating is complete. Did you have any further questions on the issue?

Thanks,
Jason

Customer: replied 1 year ago.
What kind of help did I get from you??? to put engine apart and inspect why it is knocking????
Expert:  Jason replied 1 year ago.

I'm sorry I don't understand. I tried to explain the other way to do it but you didn't want to run the engine. I can only explain how the problem gets diagnosed, if you are not willing or able to do the steps yourself then i'm not sure what it is I can do for you here???

Expert:  Jason replied 1 year ago.

You do pay the website either way. So I do want to make sure I get all of your questions answered. Do you have any further questions on the issue?

Expert:  Jason replied 1 year ago.

Hello, I noticed no rating has been put through. The website has charged you but they will not credit me for helping you out until that rating is complete. Did you have any further questions on the issue?

Thanks,
Jason

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