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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Discussion Starter · #121 · (Edited)
That fan should be plenty large for a 4bt. How did you fit that fan to the Cummins fan hub? The pilot on their hubs is 1" and a GM fan isn't. Do you know the part # on that fan. Many of the fans for the 454 are reverse rotation (counter clockwise). You fan blade is clockwise. Might need to double check that.
The fan is for a 1970 Chevelle with 454 big block. GM part # 3976064. It's a aftermarket manufacture.
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As for how I did it see: 4BT fan options
 

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My concern was not so much on the fan blade as one the clutch assembly. How did you fit that to a Cummins fan bracket? Cummins uses a 1.00" pilot and that fan clutch for the Chevy is .625".
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Discussion Starter · #123 ·
My concern was not so much on the fan blade as one the clutch assembly. How did you fit that to a Cummins fan bracket? Cummins uses a 1.00" pilot and that fan clutch for the Chevy is .625".
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Turned the pilot down to .625" and left a .140" tall step for the pulley.
Not my best job of locating the new screw holes.
 
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OK. A bit of custom work there. Beats the heck out of paying $300 for a Cummins clutch assembly. LOL. In real life you may have few times when the fan actually comes on. The 4bt runs on the cold side unless you really put it to work. Guys running in 100 deg weather rarely have their electric fans come on.
 

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Discussion Starter · #125 · (Edited)
OK. A bit of custom work there. Beats the heck out of paying $300 for a Cummins clutch assembly. LOL. In real life you may have few times when the fan actually comes on. The 4bt runs on the cold side unless you really put it to work. Guys running in 100 deg weather rarely have their electric fans come on.
The fan clutch is a Imperial 215052 severe duty, used on a lot of vehicles. About $40.
I'm in Arizona. With the heat and the AC load the fan clutch gets a work out.
 

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1989 Jeep Wagoneer, 360v8, 727, stock for now,
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Discussion Starter · #126 · (Edited)
Spent the last week figuring out how to mount the radiator. Decided to mount it in a support frame and then mount the assembly in the factory location using the factory bolt holes. Inclined the radiator (5 degrees) like the factory, makes fabricating the fan shroud a little easier.
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The bottom support is lined with bicycle inner tube to prevent chaffing.
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The holes for the radiator mount are slotted so it can slide without tearing the flanges off. And added nylon washer to accommodate the movement.
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2.5" from the radiator core to the fan clutch
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Discussion Starter · #129 · (Edited)
Got the engine up on the run in stand,
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Ran it till it was warm and then slowly gave it full throttle, then,
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something is wrong.
 

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Ouch!
 
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Yeah, looks like the after burner on a fighter jet. Much of that and you'd have aluminum coming out the exhaust pipe. Bad injector would be a good guess. Also, since the turbo is not connected you are possibly running very rich on fuel. Too much fuel and not enough air makes for a smoky, hot engine also.
 

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Discussion Starter · #133 ·
Sent the injectors out to be tested, repaired as needed. Did a compression test, each cylinder came up to 400 psi ± 5psi on a cold engine.
 

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Late timing will cause burn after cylinder head !!
 

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Discussion Starter · #135 ·
Late timing will cause burn after cylinder head !!
My next check is to recheck the timing.
Got news from the injection shop that all the injectors tested low on pop pressure. Shop said it was a toss up between repair the injectors, labor plus parts or buy new ones. New ones are on the way.
 
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Yeah, repair vs replace injectors is pretty much a toss up. Of course that can depend on whether the replacements are genuine Bosch units or an unknown generic. Sometimes rebuilt units tend to hold their tolerance better than some new ones.
 

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Discussion Starter · #137 · (Edited)
Timing: My engine doesn't have a data plate but I do know it's a CPL 1839.
I understand the static timing is 11.5 degrees, so if at TDC the timing mark is past center (lower) that would mean it's advanced?
So if the timing pin on the P-Pump is centered and the and the degree wheel showes 2°, that means I should have a total timing of 13.5°?
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That could mean that or it could mean that the pump gear may have slipped at some point in time. Not sure if that position indicates advance or retard. If the engine were at stock timing that little plastic tool should insert smoothly if the cam pin is locked in the gear. If you should need a serial number to look up parts here are 2. 45822898 and 45321244.
 

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Discussion Starter · #139 ·
That could mean that or it could mean that the pump gear may have slipped at some point in time. Not sure if that position indicates advance or retard. If the engine were at stock timing that little plastic tool should insert smoothly if the cam pin is locked in the gear. If you should need a serial number to look up parts here are 2. 45822898 and 45321244.
I remember when I first did the timing (crudely) years ago that the timing did shift after tightening the gear nut. After doing a fairly accurate measurement on the timing I'm relieved that it's only 2° advanced.
 
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