I purchased a complete stroker kit from 440 source and spun #4 rod bearing after only two passes! All other bearing in the engine were in excellent condition. I contacted 440 source with pictures and was informed the problem was oil starvation. The engine was hot vated, engine brushed all oil passages, and pre oiled after assembly. I (assumed) that all dimensions were checked prior to shipment to customer. I only plas-i-gauged the rods and mains. I was informed that the end user was responsible to inspect all dimensions and return the defective product to be re-worked. So a word to the wise, be sure to check all products from 440source, or you will be in my situation.

Fixed

440 source would not replace or discount any amount on another stroker kit.

[quote+ I was informed that the end user was responsible to inspect all dimensions and return the defective product to be re-worked. [/quote]

They are correct.

Seriously doubt that any vendor would give any considerations on a part that failed due to the assembly. They can't control the end user's assembly errors.

Plastigage on ANY motor??? Uhh, NO.

Please tell me you can't be serious. There are many, many reasons for a bearing to spin. Any and all clearances have to be checked whether its a stock type of rebuild or high performance. It takes me hours to properly clean and prep a block before I start assembly. If unsure of yourself leave the job to a professional as its harder than it looks.

My mistake was relying on a company's reputation assuming all tolerances were checked. It was my fault for not checking. I have no concrete proof what was the cause. All i'm saying check all tolerances. Every one makes mistakes. No one makes a perfect, precision product. Just because you pay a lot of money for a product does not insure its accuracy. There are not many many reasons that rod bearings spin. Check the people that make the bearing.

Only good things to say about 440 source from me, 9.20's @ 145 in my 63 Plymouth, belted piss out of it and even split a block but stroker kit still lives. Just ordered some parts from them and 5 days later I had them in Australia.

I'm not saying don't buy their product. Just check it. Rod journals in stroker kits are not plunged ground as stock cranks. They are radius ground, and taper in a journal is easy to get. Thirty five plus years running manual machines and grinders, and you can easily find it!

My last #4 failure was caused by a bad filter...So keep looking, you starved it somehow.

This is just common sense. I doubt that I'm the only one that takes brand new things apart, checks them and cleans them before reassembling for use. Had you bought a crate motor then I'd say "maybe" you'd have a leg to stand on but even then they'd probably say that racing voids any warranty.

You've obviously got an axe to grind - you could just as easily have left their name out of the post. But most people seem to be taking their side, and rightly so.

I don't care how much you pay for parts they have to be checked with the proper tools (not plastic gauge) I paid 2200 dollars for a Callas crank From Dan (Performance Only) years ago that was shipped directly from Indy Cylinder Head. I also ordered bearings from Dan when I placed the order. Dan never touched the crank as it was drop shipped from Indy. Imagine my surprise when I miced the crank and my "brand new" 2200 dollar crank was cut .010 on the rods. Did I send it back? NO because I really needed it and didn't want to deal with Indys crappy service. ALL PARTS MUST BE CHECKED!!!!!!!!!!!!!!!!

Was not oil starved. Break in was just off mains and other rods. #4 bearing was welded on journal. My guess only, rod was too tight. Had 9 quarts of oil in 7 quart pan and swinging pick-up. Just 2 passes on motor.

So you said you checked all the main and rod bearing clearances with plastic gauge. I can't say it is accurate or not but it is close. I have used it in the past without a problem . I guess the question is: what clearance did you have when you measured on the rods, on the mains?

Could be a lot of things. Even 9 qts in a 7 qt pan will cause problems. If the oil is too high it gets beat to a froth by the crankshaft and then you are feeding the bearings with froth instead of oil.

If you don't check every rod assembly for clearance during assembly then you don't know if they are all correct. The bearings have tolerances as do the crank and the rods.

I'm wondering how many millions of engines are out there that had plastigauge used to check clearances !!! Not everyone can afford or justify the cost of the tools.

And a lot of them run for years too. Trouble is race engine clearances should be opened up some and the proper oil viscosity used. After-market cranks also have a heavy radius instead of an under-cut like stock cranks. Careful attention has to be used and the proper bearings for this application. Lots of guys don't know how to properly "set" the thrust bearing and just throw things together. I'm self taught so I know I've made lots of mistakes over the years and try to continue to learn something new every day. Lots of bad info floating around the internet forums. 40 plus years of engine building for me with 3 engines on my stands right now and another 2 in our race cars and I'm still learning and still buying tools.

That crank should grind out if you go under size on bearings. My buddy ran a .030/.030 crank for years. Finally split a cylinder lol.

Any photos?
How was the side clearances on the rods?

I run a 440Source kit also and I checked all my clearances myself as I build my own engines. Its been in the car running fine since 2011 and still holding good oil pressure. Sorry to hear of your failure. Ron