Author Topic: Anyone want to venture a guess.  (Read 544 times)

rwollman

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Re: Anyone want to venture a guess.
« Reply #15 on: August 12, 2018, 08:47:24 PM »
Chet- listened to yur video quite a few times - I can hear the knock upon acceleration - I think it might be a rod or wrist pin - do you have a mechanics stethoscope?  If not they are very cheap and really can pinpoint a noise, even a vacuum leak.  Should be available at any auto store for 9-15 bucks.   

chetbrz

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Re: Anyone want to venture a guess.
« Reply #16 on: August 12, 2018, 09:04:19 PM »
Chet- listened to yur video quite a few times - I can hear the knock upon acceleration - I think it might be a rod or wrist pin - do you have a mechanics stethoscope?  If not they are very cheap and really can pinpoint a noise, even a vacuum leak.  Should be available at any auto store for 9-15 bucks.   

You are right on my friend.  I have 3 out of four connecting rod bearings making noise.  See attached link to video.
60 meg file so probably download before running it.

http://www.1948plymouth.info/1929/images/IMG_1261.MOV

Will solution with builder, I believe you can remove shims to tighten the bearings.
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rwollman

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Re: Anyone want to venture a guess.
« Reply #17 on: August 13, 2018, 01:11:50 AM »
Chet - shims will not take care of sideplay in the rod -either the crank journal or rod is worn - sorry to tell u that but tha'ts the way it is .  If u have a micrometer you can check the outside width of the #1 rod journal (big end of rod)  and compare to the noisy ones for an answer.  Shims only set oil clearance between rod and crank.  Good luck and keep us posted.  Sounds to me as if your engine builder has a problem on his hands. 

chetbrz

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Re: Anyone want to venture a guess.
« Reply #18 on: August 13, 2018, 06:40:15 PM »
I have a great deal of confidence in the builder.  I should have never run the engine with the pressure plate in place.  My mistake.  The centrifugal force probably allow the arms to open slightly and grab the throw out bearing shaft.  After that.., it's history.  I couldn't blame the motor rebuilder for that.   

Stuff happens, now we have to focus on correcting the problem.  Chet...
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rwollman

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Re: Anyone want to venture a guess.
« Reply #19 on: August 13, 2018, 09:51:21 PM »
Chet- don't believe that incident caused your problems .  That engine has 3 main bearings and the crank is strong enough to withstand what happened.  Rods are supposedly interchangeable from journal to journal so that shouldn't cause your knock either.  You just have to determine where the wear is and then go from there - good luck

chetbrz

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Re: Anyone want to venture a guess.
« Reply #20 on: August 13, 2018, 10:56:54 PM »
Thanks for the input, When I pull the engine I'll check.  But ! There shouldn't be any wear the crank was machined and the engine has less then 5 minutes run time.
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rwollman

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Re: Anyone want to venture a guess.
« Reply #21 on: August 14, 2018, 01:06:06 AM »
Chet- I'll look thru my Dykes engine info - I think the min and max side clearances for the rods is stated there.  Will let u know if I find it

rwollman

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Re: Anyone want to venture a guess.
« Reply #22 on: August 18, 2018, 05:58:27 PM »
Chet_  How U makin outwith your engine - haven't  heard anything in a while - I was thinking that you mighht have possibly bent a rod with your mishap - they r pretty frigile

chetbrz

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Re: Anyone want to venture a guess.
« Reply #23 on: August 18, 2018, 06:37:58 PM »

Thanks for the inquiry, The motor is back in the shop.  I'll let you know what's happening once I know.  Since I have other work to be done on the car.., and to tell you the truth I am getting a little burnt out at this point. I told the builder I was in no hurry. 

?? Chet...
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rwollman

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Re: Anyone want to venture a guess.
« Reply #24 on: August 18, 2018, 10:16:57 PM »
Sometimes its best to just stop and take a breather - then start again