Just wondering if someone here might be able to help with a quick question, I have recently purchased a Perkins 4 cylinder diesel model 4.108 (50hp) that originally came out of a late 70's ford f-100 pickup truck. It has a ford bellhousing with a ford 4 speed with no reverse. I plan on doing a swap with this unit and adapting it to a different type of trans, however after a better inspection of the trans/bellhousing, starter/flywheel setup, i will need to change out the fly wheel in order to adapt a different starter and transmission. So here is the question, it appears that the flywheel is probably two-3 inches thick which is much thicker than one you'd find off a v8 gasoline powered engine, can i use a different weight/lighter type flywheel or do i need one equal in weight and do diesel flywheels in general act like crankshaft balancer???? There is no harmonic balancer on the front of this engine. Any info would be helpful...

 

The 4-108 flywheel is where all the torque is generated. They used a high mass flywheel to create rotating inertia. If you lighten the flywheel you'll loose available power from the engine. 50hp was a generous rating. I believe it's at 4000 RPM with no accessories. Expect less.
What are you trying to fit it to?

 

Sweet, thks for the reply, yes it is a 4000rpm motor and with no accesories. What my plans are is to hopefully mount a AX15 5 speed transmission to it. Now i know advance adaptors makes an adaptor to mate this trans to a ford bellhousing which this bellhousing is currently bolted the the motor, however i can't use the starter configuration, the current setup has the starter motor pointing towards the engine and does not sit like most starters next to the motor, it's right next to the trans. So in order to fix this whole thing i was going to put a different ford bellhousing with the starter motor in the normal position, which will require flywheel changes. I'm sure it can be done, some way or another even if i have to have machined wheel or something, i think what i might do is find another flywheel of the same weight have a machine shop cut new bolt holes, balance it and go from there, i'm sure there will need to be some adjustments and other things to match up first like starter ring gear and starter then pilot bearing and clutch as well. Since this motor is much lighter than a cummins 4bt, i decided to use it, i plan on installing it into a jeep cherokee unibody but i plan out changing the rear axle so it can handle the diesel. So what you think????

 

the 4-108 is a gutless wonder. If you're able to break a Dana 35 with it I'll be amazed. If you've ever driven a 4bt powered truck. Don't think this will even hold a candle to it. Think more Mercedes 220D or 1984 Rabbit D. There are bell housings available in SEA standard sizes for it. You might consider going from that to thew AX15