2.9L w/ MegaSquirt to 4.0L w/ Ecumaster Black and a Turbo build

[gaz]

Konrad,

Will you be giving this new crankshaft the Sven Pruett treatment

 

[konrad911]

Haha not sure yet, first disassemble and see where am I. Then re-read and re-think and we’ll see I’m thinking though about one thing that is a must with Porsche crankshafts. These get nitrided, that’s what it is called? This strengthens the crank where main bearings fit. A must for a crank that was reground IMHO. Need to measure my new/refurbished crank to see if all main bearings are standard. If yes, then nitriding might not be needed.

Anyone knows if these cranks were nitrided at factory? If not, this might be a good idea anyway when it’s out.

 

[superj]

Nitrided is the correct name, yes.

No idea if they are or not though

 

[konrad911]

So I decided to go with nitriding. Assuming this is an extra cost at the fectory and Ford Trucks are not Porsches I bet this did not happen.

I used to live in a big city where I had a big machining shop that did all I wanted, now I live in the middle of nowhere. The difference is I need to find good experts and services all by my own, which takes time and driving around but costs like a half as I learned.

Just had a chat with a specialist at a company that is doing „ADVANCED TECHNOLOGIES OF HEAT TREATMENT AND HEAT-CHEMICAL PROCESSING”. They will do the nitriding, but asked a million questions about the material the crank is cast from, the depth of the nitriding layer I want and so on.
good enough the guy I talked to was patient enough and explained me what the process looks like and also what they usually do with the other cranks

The cost is in range of $40-$50 so while I’m there it’s certailny worth to do it.
The drawback is I need to bring the crank there by myself (best) and it’s over 1.5 hour drive one way. This is rather long for Poland where I live I’ve been in the US few times so I know that for you guys it’s almost like doing local groceries

i’ll keep you posted

 

[konrad911]

Today early morning I found a few minutes to measure the crank.
Seems the main bearing journals are very close to STD and the big end even closer (see photos).
Checked all of them and the measures were exact to the possibilities of measurement of my tools

The woodruff key seems to be stuck though. I sprayed it with WD40 and will try in the afternoon to remove it.

 

[alwaysFlOoReD]

Hi, I was reading this article for other reasons and thought it might interest you.

Ford 4.0L V6 Engine

Exploring the Ford 4.0L Engine: Evolution, Components, and Rebuilding Tips for Rangers, Explorers, and Aerostars. Learn more here!

www.enginebuildermag.com

 

[konrad911]

Thanks, I know that article. Based on that I ordered the 97 crank. Hope this will confirm in practice

 

[Shran]

@PetroleumJunkie412 is going to shit a brick when he sees you swapping a 2.9 for a 4.0.

I, on the other hand, cannot wait. Cool project! Keep us updated!

 

[konrad911]

So I was reading through the chapter about crankshafts. Forgive my technical English but I want to understand.
The deburring term in relation to crankshaft would be grinding off any sharp edges that were formed either from casting or grinding or drilling? Like chamfering the oil holes in the journals but also removing any excess material where two halves of the casting forms joined?

 

[gaz]

Konrad

You are correct, regarding deburing.

 

[konrad911]

I did take a closer look at the crank today... Well, let the photos tell the story of the quality of the casting...
The good thing is the oil passages in the journals are chamfered. Not sure though if by factory or the company I bought the crank from (it supposed to be crack tested and bend tested and in STD sizes). I am curious how the crank I currently have in my 4.0L on the stand looks like - will be interesting to compare.

For sure I will do some grinding, chamfering and so on. I'm just thinking whether I should grind ALL the casting structure flat? (That area that was not machined and looks like depressed sand in iron I mean). That's a question mark, but from the perspective to reduce any points that could be the beginning for the cracks later on I think this should be completely flat. I need to check if in an old Sunnen book for engine machining there is anything mentioned for the deburring process...

I guess this adds additional weeks to my build, but I just don't cut corners... (but for sure some I will, with a grinder )

 

[gaz]

@konrad911 ,

Everything you have circled/highlighted are areas to deburr/clean up. When I do this to a crank, I follow Sven's guidance, nearly to the letter; in my experience, the results are worth the effort!

 

[alwaysFlOoReD]

In my unprofessional opinion, there is no need to grind the rough sand casting tho there is no harm either as long as there is no major removal of weight. Talk to the machine shop that does your crank balancing and see if they think it's ok to knife edge or smooth the counterweights. The sharp machined edges I would maybe take the edge off. I dont think there is any reason to worry about cracks forming from the holes drilled in the counterweights as there wouldnt be any force but centrifugal operating there. I also think there is the possibility of introducing problems if you're not careful.

 

[konrad911]

Well well… if I will go for shot peening, and most probably I will, then making the rough casting surface smooth is a must IMHO to get the surface evenly hardened. And just after all of that crank will go to nitriding. At least that in my understanding is a fully prepared crank.

I’m not that much worried about imbalance of the crankshaft after bits of grinding. This will remove the material rather evenly, so this will impact the crank balance if at all just slightly. I’m not planning to remove any bosses or so. Just to make the surface smooth in touch. No sharp edges.

@gaz - what tools you find best for deburring process?

I ordered the 8 bolt flywheel that will accommodate the 10.125” clutch.

I’m getting worried for my tranny now

 

[gaz]

@konrad911 ,

The best tool to use is a ¼" driven electric or air handheld grinder with the appropriate shaped rasp (cutting head). It is good to have an assortment of different shaped rasps and cutting heads. An electric Dremel could be used but the time required and cost of materials would no dought be higher.

Then finish using drum sanding with the same tool; I use 120 grit then 240 grit and DONE! I do have my machinist knife edge, polish and then perform a complete bottom end balance.

You can also use a cut off wheel and feather and fare out the areas you chose.

I remove every mark, marking, casting, all <90°'s getting a chamfer and all edges >90° get rounded. I removed all roughness but did not go for a mirror, just fared, smoothed.

While i haven't had the need to peen the my cranks, having them peened would be the appropriate next step. After I perform this process on my connecting rods, they are off to get peened (plus ARP hardware).

I prep the block and main caps and to a much lesser degree the pistons. The only component I do not do this on is the cam.

Two other components that benefit from this treatment are the water and oil pumps.