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i cant afford to pay a shop to do it so i am thinking of doing it my self. i know my way around tools and i have rebuilt gas engines but never a diesel. what i need to know is what rebuild kits are good out there? i seen dap offers one. or should i just go to cummins and get one. i found a machine shop in my area that is supposed to do diesel engines so i am gonna go there tomorrow and see what they charge to do the machine work. the reason i am gonna rebuild is i am getting really bad blow-by it even popped my tappet cover i installed and is blowing oil out there. the truck has a little over 200,000 miles on it but i bought it used. any tips or advise would be greatly appreciated.  

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The machinist should have those specs if he does it for a living, he should be able to measure in certain spots to see how much has been removed from stock. The other way is after the rotating assembly has been assembled and measure how far from the top of the deck the piston is at TDC there are specs for this as well as the head dimensions.  Like I said the machinist better have these numbers if he is doing it for a living if not he has no business building engines.

 

Most machinists will actually have things all measured out and tell you during the job what you will need for bearings and gaskets or when he gets done machining your engine, at least all machine work I have ever had done which is a lot they have all let me know what is needed during the work.

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is it true you loose compression and HP when you use a thicker head gasket.  

Nope.................The reasons for a thicker gasket are, a milled block deck or head surface to get it back close to stock  clearances, or if one is running high levels of boost pressure and need to increase the dimension to reduce cylinder pressures a bit, the other reason is if running a different style of piston or cams with higher lift rates and the clearance is needed between valves and piston crowns. The piston rings control compression. The difference in power would be so slight it would not be noticeable if at all.

This  'Jasper'  engine  may  have  some real  surprises  awaiting you...   (well,  apparently  it  didn't  fare too well on last  build)..        WF  nailed it  with   measuring   deck thickness...  I'd  sure  find out  what  minimum  needs  to be  for both the  block and  head...    and  MEASURE  what the  injector  protrusion   is!!!      The more that is milled off the   head,  the  more it'll protrude,  and  melt  either itself,  or  the piston.   Shims  make up  the difference if needed.    You  may  have  a  head  that's  been   hacked  a  terrible amount..  and   might be the reason  for your  flamed-out  cylinder/piston.    Did you notice  any difference  in   the  sealing rings  on the  injectors   from  cylinder to cylinder?

 

If  you can't  find the specs on the  deck thicknesses,     measure   the  top of piston @tdc   to  top of  block...,    then   put in a  standard thickness  sealing washer  under the  injector,  torque it  down,  and  measure  protrusion.     Compare  those  readings  with   cummins  specs.

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heres something to throw at you guys to see what you think. is there such a thing as a good machine shop that is not as good for putting a engine together as they are for doing the machine work?  the reason i ask is i met a guy once who was a insurance agent. he worked for a auto parts store when he was a young man doing the machine work. he told me he was a good machinest but he never put the engines together, another guy did it.i always thought how the hell can that be.  then when i was looking for a machine shop to do this engine i went to a shop and talked to the guy he said he could do all the machine work. then i asked how much to assemble it he said he just does the machine work his partner does the assembly. that kinda through me for a loop cause i always thought a good machinest should be able to assemble a good motor. but the more i read my dodge shop manual and read on here it seems that there is a lot to know and do rather then just put it together.

It's  the  'particulars'   specific to   each  engine  (such as  your  injector  protrusion)   that  makes up  the   difference  in  assembly  quality.

The machinist  already knows  what  the  clearances  need to be,  (oh boy,  he BETTER  KNOW)   ie;   rod bearing, main bearing,  piston wall,   etc...  

 

Some  shops   have   specialists,     and  it  makes  for  a more efficient  shop.      The machinist  only  deals  with  the never ending  pile of  iron coming in the door,    and   can't be  distracted.   Plus,  it's  a lot easier to keep  the  assembly area  clean  if  not  running back and forth from the   tear down,  machining  area  too.

 

Then  there  are    shops  that  have  guys  that'll  follow  the  engine  all the  way  through the end.

Edited by rancherman

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well i went to the shop today he ran down everything to me that he was gonna do and i met his guy who does the assembly i seen a engine block that he was working on and he looks like he knows all the ins and outs so that put my worry's at ease. turns out the owner does the head work and he has this old timer come in who does all his assembly work, kinda of retired part timer. pretty picky guy too, compared to some other shops i seen. the owner said he is gonna check the head and see how much was shaved and the assembly guy was gonna do the same on the block, to see if he needed to really go 20 over or 10. the old head gasket was ,20 over already. i was kinda worried he was just gonna slap it together cause i never used him before. thanks for all the info guys  

  • 2 weeks later...
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well my engine is finally done. gonna try to pick it up tomorrow. he had to get a engine done before mine. i went ahead and ordered the  Goerend  TQ it came with a limited life time warranty so far i'm into this engine $2,800 to get it rebuilt, parts and labor. i still have to order a rebuild kit for the turbo. and a pyrometer gauge. later on i'll do VB swap, pretty much tapped out. thanks for your help guys and i will keep you posted.

 

The best converter in the world is no better than a stock one without added pressure from a modded VB. A stock converter would last a lot longer even with a modded VB, on a near stock engine a stock converter with bumped internal line pressures from a VB would be near bullet proof if driven with common sense.

Well, its comforting to know they can be rebuilt for less than the transmissions!

Rebuilding transmissions isn't that expensice except when buying expensive aftermarket parts, you are in part paying for a warranty period built in to the price. For a basic tranny rebuild parts only cost a few hundred bucks unless you have shaft or planetary gear issues then the price explodes fast.

 

His engine is being done at a machine shop which labor rates can be cheaper than normal shop rates plus he didn't mention any crankshaft work either which saves a lot of money overall too. When it comes down to just boring and sleeving the cylinder bores it is pretty reasonable when added to a basic rebuild kit minus main and rod bearings, If the main and rod bearings looked good then they can be reused and save a bunch of money too.

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yeah i lucked out. the cam and crank were in great condition. so no work there. i bought  complete cummins so all new bearings even if they didn't need them. would of been cheaper if i went aftermarket. only had to replace one piston though. and if i would of assembled it it would of saved me $700 too

I spent $4500 on my transmission rebuild. Darn near half was in labor. I had to have the OD unit replaced as well. If I would have taken the dive and did myself at the time, I could of had a pretty bullet proof transmission!

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i have a quick question. before i install my injectors do you think i should have them pop tested? there brand new bosch rv injectors with no more then a thousand miles on them. and can you tell me how many quarts of tranny fluid it takes to fill up a TQ ?

I can't remember exactly but it's something like 2-4 quarts. I'm leaning towards 4 because i think i dumped in 2, then you wait for the clutch material to absorb some fluid, then top it off. Or it spills out when you turn it upright.

  • 2 months later...
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well here is a update. the engine runs like a champ ! i do have a front main seal leak, my fault should of took my time. and my vacuum pump has a leak so i have to pull it and put a new seal in it again, already rebuilt it before i did the engine. i ended up putting a goreand TC in at the same time. pretty pricey but it works great. was heading to tucson, az lat week and was checking to see if a spare dually rim i had fit and ended up finding out my Driver side hub bearing is worn out so now i have to replace it. just got a timkin from rockauto for 189 with abs so i will change tomorrow. just wanted to say thanks for helping me guys. 

Good to hear its alive again, did you have the injectors checked before reinstall in rebuilt engine and did you go with a modded VB to feed the pressure to the new TC?

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no i didnt get the injectors pop tested they are brand new from bosch. not rebuilts so i am just gonna run them. the mod vb is next after i take care of the oil leaks

Ever find out how much was ever milled off the block or head and what thickness head gasket was needed?