Machine shop fail

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erikroy57

Well-known member
Joined
Nov 16, 2016
Messages
46
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5
Location
Montreal
My Car
1973 Mach 1
So i bring my 351C short block to a local machine shop to get it done. They told me the harmonic balancer is crap and i need to buy a new one ... im ok with that, they are the professionals so they buy a new one. Few months later, when i get the engine, i started to build the rest of the engine. Just before putting the heads, i realize i cant bring the rotating assy to TDC on the damper pointer. A quick search on the internet, and i realize those guys buy a Windsor harmonic balancer, which is quite different than a Cleveland. Windsor have 3 bolts and 28oz, vs a cleveland that got a 4 bolts and 50oz.

I called the shop, they expressed that they are sorry, and then order the new one.

Now, the concern i have, is that he has telling me that, on the process of rebuilding the engine in their shop, they put the crank shaft with the damper on a calibrating machine to ensure the crank is good. Now since the weight of the cleveland damper is quite different, this calibration is completely f***ed off. He said he will have to machine the new damper to reduce to 28 oz to give my an equivalent damper to what the crank is calibrated to now.

Im then guessing i will received a crappy balancer, without the black anodize finish and with crappy tdc marks.

What should i do, and what crappy results will i get with all this ?

1st balancer (wrong one): PB1009ST

2nd balancer (right one): PB1082ST

 
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Well you have to see what "balancing" they did of the internal components so that the correction of the balancer issue doesn't effect the NON internal change.

When I see 50 Imbalance, that is a a LATE windsor - there are 28.2 earlier ones too. (this also is why some are 3 bolt some are 4 bolt/later)

You really have to start over to see WHAT THEY DID. I know other will say RUN AWAY ....but right now you have to get all the info so you can move forward , fix etc etc

Mark

 
Surely the company will fit new harmonic balancer and balance everything up. Its their mistake so they should make it right. I would take a ride to the shop and ask EXACTLY what will be done to rectify THEIR mistake

 
I see making a dumb mistake to order the wrong balancer but shouldn't they figured it out whaen it was 3 bolts instead of 4. It should have not fit. Or maybe there was a 4 bolt version.

Sent from my SAMSUNG-SM-G930A using Tapatalk

 
All small block Ford engines, including Cleveland's and "M"s, had 28 ounce external balance up through 1981. In 1982 they went to 50 ounces.

All Cleveland's had 4 bolt harmonic balancers, 302s and 351 Windsors could have had either 3 or 4 bolt balancers. They are not interchangeable. The Cleveland diameter is 6-1/2 inches, the 302 and 351 Windsors are 6-3/8", and the snout lengths are different.

 
All small block Ford engines, including Cleveland's and "M"s, had 28 ounce external balance up through 1981. In 1982 they went to 50 ounces.

All Cleveland's had 4 bolt harmonic balancers, 302s and 351 Windsors could have had either 3 or 4 bolt balancers. They are not interchangeable. The Cleveland diameter is 6-1/2 inches, the 302 and 351 Windsors are 6-3/8", and the snout lengths are different.
You re seems to be right, according to summit they are both 28oz (cant find this info anywhere else)

Why did he told me 50 from the shop :S

 
Whoever you're talking to doesn't know what he's talking about, or he's going to try to put on a Windsor 50 ounce balancer. Both the harmonic balancer and the flywheel (or flexplate) have to have the 28 ounce external balance, and both have to be on the engine for them to dynamically balance the engine.

 
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The shop is clearly incompetent and did NO research when they realized they knew NOTHING about a 351C. It sounds like there is a real possibility that the entire rotating assembly will need to be rebalanced. I would demand a complete refund and start the search for a machine shop that does know 351Cs. The good news is, you found it before the engine was in the car and you started it. I hate hearing stories like this. Unfortunately, it happens a lot. I wish you the best on the build. Chuck

 
Erik- I have to agree with C9zx. You need to push this and obtain a refund, and find a competent shop. I love Montreal, used to get there quite a bit. I remember a great goaltender with your same last name. There has to be a history of working on classic US V8 engines in Montreal, and you should be able to locate a much better shop. Who knows what other corners would be cut if the original shop were to try and "correct" this problem.

 
Updated !

Machine shop guy agreed to come by to my home to bring the engine back to his shop to redo the works.

He said it is less works for him to rebuild the engine and re-balance the crankshaft than machine a damper to fit.

 
Damn,

I don't know if I would have let them fix it. I probably would have went to a different shop for the fix, then sue the first shop for the repair cost.

 
Send it to Ed Wien's Racing and Pro Shop it Niagara, Ontario. He rebuilt my original 429 engine a couple years ago and he knows his stuff. We have the same problem here in Ontario, not many shops can build a good "old" engine these day's. Had I not found Ed, I would have been taking my engine to the USA...

 
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