Knocking after seafoam

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Knocking after seafoam

Unread post by Guest » Wed Nov 20, 2019 9:08 pm

I used seafoam about two weeks ago but did not have engine running I just poured it I to the hose from intake then I tried to start it wouldn't. Until I realized it could possibly hydrolocked so i took all my plugs out and turned the harmonic balance to get out the seafoam that remained. My truck started right up..but is now knocking. Could it be because I still have seafoam in my cylinders? My oil is fine.

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carriedi
Posts: 2302
Joined: Wed Apr 10, 2013 12:42 pm
Location: Oregon

Re: Knocking after seafoam

Unread post by carriedi » Thu Nov 21, 2019 11:53 pm

there is a possibility that there is engine damage from being hydrolocked. Piston damage, wrist pin damage or connecting rod damage can happen when the starter starts to spin up and then hits a cylinder full of a liquid. For all practical purposes liquids don't compress. If you just get a lock up that would be nice. Sometimes the engine starts to spin and you get the engine momentum going, it hits pretty hard and things get damaged.

What kind of knock do you have? Is it like a lifter knock? Rod knock? Piston slap noise? Engine ping? Does it get louder with engine speed or load?

Guest

Re: Knocking after seafoam

Unread post by Guest » Mon Jan 20, 2020 7:13 pm

More like a slapping noise and it gets faster but slightly quieter as well. Someone told me it could he my knock sensors..but I cant find them

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carriedi
Posts: 2302
Joined: Wed Apr 10, 2013 12:42 pm
Location: Oregon

Re: Knocking after seafoam

Unread post by carriedi » Wed Jan 22, 2020 8:36 pm

I don't know why someone would say your knock sensors would cause your problem after using seafoam. Knock sensors listen to the engine to change the timing if it thinks the engine is pinging from detonation. You should take your car to a shop and have them just listen to the noise and have them give you a opinion on what they thing it is. Without hearing the noise myself anything I say can't mean anything.

My opinion is just from the information you gave me. there may be other things going on with you engine I am not aware of. Hearing the noise makes a big difference. See a local shop.

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