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Discussion Starter · #1 ·
Hey guys,
Not alot of options for available parts here in OZ other than paying Cummins tax for OEM parts.
One of the local guys sells these top end kits and was wondering what the quality is like? Would I have any issues in using one of these kits, short term/long term?
Possibly looking at cracked head or gasket so want to get parts ready if I need to pull the head.
Flip side, if Im pulling the head, any suggested upgrades? Currently running VE pump, standard injectors, standard timing(as far as I know) HX30w and front mount IC. Boost and power is a bit laggy at low speed, Looking to get a decent amount of power as we tow a 1.5t camper reasonably regularly.
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In general, the aftermarket gasket kits are OK. Every so often you run into one where the head gasket is absolute junk. It's interesting that the kit you are looking at there is $275 you cost where it sells for $91.23 here in the USA. Darn expensive to get it to you. 4BT 8v 3.9L Cummins Upper Gasket Set Here are 2 videos you might watch that show what to be aware of in the head gaskets.
 

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1972 F250 4x4, 78 d44, 3.55, np205, 200hp 4bt nv4500 in progress
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I'm a newb but rebuilt a 4bt using mostly mcbee parts upper/lower gaskets and pistons/rings/bearings. Pistons and rings had no appearance of cheap rough or chinsy. I measured ring gap (.020 over) and all rings were in spec min/max. I bought mcbee rod and head bolts and they appeared to be a virtual match to the takeoffs. Taking a gamble on it and will not know until down the road, and I'm hesitant to recommend anything as it could put someone else in a bind.

Seems as though some of the oil pan and covers gaskets might have been a little less stout as the cummins. Rear main seal came with installer tool.

I bought the cummins head gasket as it sounds like that was an area to not use anything else.
FWIW
 

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Discussion Starter · #4 ·
Unfortunately Cummins OEM parts here in Australia require selling a kidney and donating ya left nut.
How much do you guys pay for an OEM head gasket in the US?
 

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es, you live in a land where things that we consider cheap tend to cost a considerable amount of money. Outside of the arctic region, yours is about the only continent where Cummins doesn't have a factory to make parts. We used to have a guy on our forum from Australia and he had a friend who imported from the USA. He bought parts here and got them shipped in a container with the stuff the guy was importing so there was no huge expense. Even small parts like gaskets there is about only air or sea shipping to get to you and air is horribly expensive. You ask about gasket prices. Well, that varies all over the place. Here's a listing for a Cummins brand 4bt head gasket for $59.87. Amazon.com At a Cummins store you may pay double that or more. That part 3921393 is an obsolete part. Like many Cummins parts it has been replaced several times. The current part is 3283333 which costs about $100. Of course you must be careful on head gaskets depending on whether your engine block has been surfaced. The amount of piston the extends above the block surface dictates whether you need a thicker gasket or a larger bore if the engine has been bored oversize. Those gaskets are up to 50% more expensive. The company Mahle/Clevite makes gasket kits for the Cummins and they are one supplier for the OEM gaskets. Here's one of their complete head kits for $113.59. That's all the gaskets and seals attached to the head. MAHLE HS4961 HEAD SET 3.9L CUMMINS 4BT
 

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Discussion Starter · #6 ·
es, you live in a land where things that we consider cheap tend to cost a considerable amount of money. Outside of the arctic region, yours is about the only continent where Cummins doesn't have a factory to make parts. We used to have a guy on our forum from Australia and he had a friend who imported from the USA. He bought parts here and got them shipped in a container with the stuff the guy was importing so there was no huge expense. Even small parts like gaskets there is about only air or sea shipping to get to you and air is horribly expensive. You ask about gasket prices. Well, that varies all over the place. Here's a listing for a Cummins brand 4bt head gasket for $59.87. Amazon.com At a Cummins store you may pay double that or more. That part 3921393 is an obsolete part. Like many Cummins parts it has been replaced several times. The current part is 3283333 which costs about $100. Of course you must be careful on head gaskets depending on whether your engine block has been surfaced. The amount of piston the extends above the block surface dictates whether you need a thicker gasket or a larger bore if the engine has been bored oversize. Those gaskets are up to 50% more expensive. The company Mahle/Clevite makes gasket kits for the Cummins and they are one supplier for the OEM gaskets. Here's one of their complete head kits for $113.59. That's all the gaskets and seals attached to the head. MAHLE HS4961 HEAD SET 3.9L CUMMINS 4BT
Thanks Char.
So without knowing the history of the engine due to this being a conversion, I'm walking into a bit of unknown until I open it up? I can spin spanners and build stuff following RnR steps, but measuring piston protrusion and over sized bores is a bit out of my scope of experience.... happy to learn though and more tools in the shed always helps!!
I don't have a mountain of cash to throw at it otherwise I'd probably be looking at tidying up the bottom end too.

On a side note this engine I have had balancing shaft bottom end but believe the guy that done the engine swap removed the balancing component from the bottom end. Engine shakes to shithouse on shutdown and assuming this could be part of the problem with removing the balancing parts. Looking to get hold of a Fluidampr soon but is there any way to reduce the 'shake'. ESN is 44127375
 

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On the issue of shake on shut down that is the engine telling you it doesn't want to quit. LOL. The firing order contributes a lot to that. The Fluidampr unit will not help that. It will improve smoothness when running. Cummins offered a similar unit on marine units and no it wasn't cheap either. Around $600 US or a bit more. That thing weighs like 24 lbs. A 4bt doesn't have harmonics like the 6 cylinder so bolting on a balancer from a 6bt has little to no effect. That bottom end balancer you mentioned was a very special part mainly used on generators. It has a max engine speed of 2000 RPM so it can't be used on a road vehicle. I've only ever seen 2 of those. When new they were horribly expensive. Around $6000 US. As far as working on a 4bt it is most wrenching. If you had about 4 tools you could do most of the other measurement work. You'd need a hole gauge to check piston bore, a micrometer to measure that, and for the piston protrusion you'd need a dial indicator gauge and a magnetic base. Bearing clearance on the crank can be done with plastigauge.
 
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