I have a 4BT with about 180K that I am going to throw into this land cruiser I am building. The engine is out now, mostly clean now also, and in need of complete regasketing including the head gasket (which leaks oil & coolant out the side) but the motor itself runs great and is actually super powerful. It might have slightly low compression but if it does, it is minimal would be my guess. I put over 1000 miles on the bread truck before the rebuild, as I said ran great. Havn't done a compression test yet but plan to, but need to replace the head gasket regardless...
Cummins complete gasket kit is about $600.. Rebuild kit about $700 or $800 if I remember correctly, using OEM. There are some cheap aftermarket rebuild kits that are name brand as low as $500 shipped. I would probably not consider one of these for the piston parts etc, most likely, except unless I choose to not rebuild and only use the kit for the gaskets, as its cheaper than OEM and gaskets are not as important. I would probably need to buy a second Cummins headgaket regardless as Cummins recommends you use a thicker headgasket to replace any metal removed in the head milling process. And they only sell the thicker gaskets separately and they are $50 each so not that bad.
Question is, I haver never rebuilt an engine before. I have good technical knowledge and ability and now think I would probably be fine.. But seating the pistons right, the measurements etc that are needed to do this (correct??) - or do you simply bolt all the new stuff together on the crank, use thread locker and torque wrench and you are good to go with a diesel? Any feeler gauges/precision measurements that I will have to do that requires "special knowledge?"
I was reading this thread about good techniques to get the pistons to seat right. This is on V8 gassers but I feel that its probably the same basic thing for diesels...? Here is the link:
http://www.circletrack.com/howto/4639_maximum_power_piston_rings/
( <-- Good reading I feel like regardless )
I have no problem doing everything mentioned in the article except it is a little confusing for me using the feeler gauges, etc. And the piston leveling tool, bot can probably figure it out? But I do have the big thick 600+ pages Cummins manual that I think goes though all this?
RE machining, here is the ala carte menu for machining from my favorite machining shop that is very competent and well known & respected...
$65 head milling
$220 head milling and valve grind (probably required is my guess)
$60 cylinder honing
$90 block deck mill
$125 cyl boring including honing
$125 crank grind...
Here's a cost breakdown of what it will cost according to requirements:
- Head milling alone, best case scenario, $65.
- Head + valves, head gasket job only, $220
Machining if rebuild the motor:
- If everything OK valve wise (probably doubtful) + cyl wise, head + deck mill, cyl honing: $215
- Valve job needed, head + deck mill, honing. $370
- There is some scarring in the cyls, $450
- Scarring in cyls, need a crank grind too.. $575
All this, plus parts (+ tax)...
So far, this whole truck has been an expensive build, pretty much everything on the truck is new or rebuilt, truck is/will be entirely restored, but problem is I am running out of money and am fairly poor right now, literally every spare cent right now is going to it, I have probably about 70-80% of the stuff bought already now and almost all big ticket items paid for already. If I tore this stuff apart, at this point hate to say, but it would probably take a few months to get the $$ to put everything back together...
Also, I am a little "scared" I supposed because I havn't ever rebuilt a motor before. Also I am wondering if I should do all this too because the engine runs well so far...
I guess I should wait an see what the compression test says? Anyone have any advice on rebuilding techniques or is it relatively easy you think? I have done all sorts of crazy machanic jobs, probably over 6 headgasket jobs, timing belt/gear jobs, including on several fancy fuel injected cars and other diesels. Never rebuilt a transmission myself but am a pretty capable, smart, and patient/cautious mechanic.. I can also probably dig up a friend or two who has decent engine rebuilding experience to maybe help me out probably, I would have to bribe them with something, but probably worth it..
I talked to a local diesel engine rebuilder/specialist, and he said "180K on a B series - nothing at all, I wouldn't rebuild it, replace the head gasket, do the cheap gasket kit, and call it quits." Then I'd be in it probably less than $700 which I could do a lot easier than $1500 or so I think at this point..
Then I am also weary as engine runs great now, what if I did all this and the pistons didn't seat right or something like that.. Of course I will take every step to break in engine correctly, but sure would be a bummer if I went to all this time + expense for nothing, when engine ran great before... But that said, I like the idea of a fresh rebuild to match the rest of the car...
Thoughts / comments?
Cummins complete gasket kit is about $600.. Rebuild kit about $700 or $800 if I remember correctly, using OEM. There are some cheap aftermarket rebuild kits that are name brand as low as $500 shipped. I would probably not consider one of these for the piston parts etc, most likely, except unless I choose to not rebuild and only use the kit for the gaskets, as its cheaper than OEM and gaskets are not as important. I would probably need to buy a second Cummins headgaket regardless as Cummins recommends you use a thicker headgasket to replace any metal removed in the head milling process. And they only sell the thicker gaskets separately and they are $50 each so not that bad.
Question is, I haver never rebuilt an engine before. I have good technical knowledge and ability and now think I would probably be fine.. But seating the pistons right, the measurements etc that are needed to do this (correct??) - or do you simply bolt all the new stuff together on the crank, use thread locker and torque wrench and you are good to go with a diesel? Any feeler gauges/precision measurements that I will have to do that requires "special knowledge?"
I was reading this thread about good techniques to get the pistons to seat right. This is on V8 gassers but I feel that its probably the same basic thing for diesels...? Here is the link:
http://www.circletrack.com/howto/4639_maximum_power_piston_rings/
( <-- Good reading I feel like regardless )
I have no problem doing everything mentioned in the article except it is a little confusing for me using the feeler gauges, etc. And the piston leveling tool, bot can probably figure it out? But I do have the big thick 600+ pages Cummins manual that I think goes though all this?
RE machining, here is the ala carte menu for machining from my favorite machining shop that is very competent and well known & respected...
$65 head milling
$220 head milling and valve grind (probably required is my guess)
$60 cylinder honing
$90 block deck mill
$125 cyl boring including honing
$125 crank grind...
Here's a cost breakdown of what it will cost according to requirements:
- Head milling alone, best case scenario, $65.
- Head + valves, head gasket job only, $220
Machining if rebuild the motor:
- If everything OK valve wise (probably doubtful) + cyl wise, head + deck mill, cyl honing: $215
- Valve job needed, head + deck mill, honing. $370
- There is some scarring in the cyls, $450
- Scarring in cyls, need a crank grind too.. $575
All this, plus parts (+ tax)...
So far, this whole truck has been an expensive build, pretty much everything on the truck is new or rebuilt, truck is/will be entirely restored, but problem is I am running out of money and am fairly poor right now, literally every spare cent right now is going to it, I have probably about 70-80% of the stuff bought already now and almost all big ticket items paid for already. If I tore this stuff apart, at this point hate to say, but it would probably take a few months to get the $$ to put everything back together...
Also, I am a little "scared" I supposed because I havn't ever rebuilt a motor before. Also I am wondering if I should do all this too because the engine runs well so far...
I guess I should wait an see what the compression test says? Anyone have any advice on rebuilding techniques or is it relatively easy you think? I have done all sorts of crazy machanic jobs, probably over 6 headgasket jobs, timing belt/gear jobs, including on several fancy fuel injected cars and other diesels. Never rebuilt a transmission myself but am a pretty capable, smart, and patient/cautious mechanic.. I can also probably dig up a friend or two who has decent engine rebuilding experience to maybe help me out probably, I would have to bribe them with something, but probably worth it..
I talked to a local diesel engine rebuilder/specialist, and he said "180K on a B series - nothing at all, I wouldn't rebuild it, replace the head gasket, do the cheap gasket kit, and call it quits." Then I'd be in it probably less than $700 which I could do a lot easier than $1500 or so I think at this point..
Then I am also weary as engine runs great now, what if I did all this and the pistons didn't seat right or something like that.. Of course I will take every step to break in engine correctly, but sure would be a bummer if I went to all this time + expense for nothing, when engine ran great before... But that said, I like the idea of a fresh rebuild to match the rest of the car...
Thoughts / comments?