motors motors motors

[red]

Well finally picked up a 6.5 yesterday for my truck, hopeing to install it in the next 2 months.

For those of you who have not been following this truck and the issues I've been having heres the rundown. It's a 1987 chevy crew cab long bed (9 foot flatbed) dually on a 6" lift and 35" tires that I use on medium difficulty offroad trails and for towing. When i bought the truck it had a good running 454 backed by a sm465 and np205. After alot of research I had decided to convert it to a 12 valve cummins, nv4500 and np205 with engine goodies. Got the engine and trans in after months of fighting with discontinued parts that people wanted fortunes for, and finally had enough of that when it came to the tcase so pulled that drivetrain back out and sold it. Was wanting to drive my truck again (had been 5 months) so i decided the cheapest and easiest route would be to go back to a big block gasser. Sadly about this time I no longer had a shop to work in so I had to drop the truck off at a mechanics shop. Fast forward through the issues there it took me 7 months to get my truck back :cussing: and it had alot of issues from their install. Fuel lines ran incorrectly (somehow got the mechanical fuel pump to work off of its return line and had capped the main line), clutch throwout bearing was installed incorrectly, brand new hydroboost pump squeals, engine has an oil leak, and the starter grenaded (that made 14 for this engine block since i've had it, thank god for free replacement warranties).

After I fixed their mistakes I broke the motor in, changed its fluids, and made the trip from northern Utah back to west Texas since my military enlistment is now over, going to work oilfield. Motor pulls wonderfully, just cant pass a gas station to save its life haha. Gets 7-8mpg cruising at 60-65mph (2250-2500rpm). Motor has been bored 30 over, exhaust valves enlarged, dual plane intake manifold, 750cfm carb, long tube headers, and a custom cam for torque in the low-mid range.

Back on topic, that kind of fuel economy on the highway makes this thing prohibitive to drive since most of its driving is long distance highway. I decided to go with a built 6.5 because of the simplicity of the conversion, and the cost factor.

Thanks to deejaa I now have a 6.5 that was installed in a 92 c3500hd. motor was a crate engine that was installed in 2004 so i'm curious if its a new block, will hopefully find out today. has a mechanical injection pump, 130-140k miles on the engine, and as it sits right now fires right up and sounds healthy.

Today I will be draining the oil, putting the motor on a stand and pulling the pan to inspect the mains. Does anyone have the part#s for the main studs? Thinking of running a stud girdle as well, any other upgrades to run on the bottom end? The goal for the motor is to be in the 500-600ft/lbs range reliably (I know pushing the motor).

Current plans for the motor consist of:
1. Main studs
2. stud girdle
3. Lowering compression to 19 or 20:1, not with head gaskets
4. diamond precups or just enlarging the ones that it has
5. Head studs
6. ATT turbo
7. Intercooler, I have one that is already modified to fit from when the cummins was going in
8. 2.5" crossover and either a 3 or 4" downpipe. Problem here is getting the exhaust to clear my t-case since the truck is a passenger side drop t-case.
9. high flow waterpump
10. Dmax fan
11. Dual t-stat housing

Debating whether to run the stock manifolds which might run into my ac box or possibly build custom ones that will flow better. The truck has a high clearance engine crossmember from off road design that moves the engine 3" forward and up 2"

 

[deejaaa]

wow, sounds good. dual crossover, will need to modify throttle cable mount. if is the update you won't need girdle. *fingers crossed*

 

[WarWagon]

Current plans for the motor consist of:
1. Main studs
2. stud girdle
3. Lowering compression to 19 or 20:1, not with head gaskets
4. diamond precups or just enlarging the ones that it has
5. Head studs
6. ATT turbo
7. Intercooler, I have one that is already modified to fit from when the cummins was going in
8. 2.5" crossover and either a 3 or 4" downpipe. Problem here is getting the exhaust to clear my t-case since the truck is a passenger side drop t-case.
9. high flow waterpump
10. Dmax fan
11. Dual t-stat housing

Debating whether to run the stock manifolds which might run into my ac box or possibly build custom ones that will flow better. The truck has a high clearance engine crossmember from off road design that moves the engine 3" forward and up 2"

That is quite the battle to get your truck going. Maybe a different gearing to lower the RPM's of the big block would get better MPG's for you.

I would change the list with reason given. 1st you need to check for cracks before you even start. Second, I wouldn't even touch the main bearing bolts as I feel they are best left alone to avoid additional stress of taking them on and off. You should line boar the block after adding main studs and the studs and girdles don't have that good of a rep for preventing cracks.

Current plans for the motor consist of:
1. Main studs ** skip it.
2. stud girdle ** skip it
3. Lowering compression to 19 or 20:1, not with head gaskets
You are after MPG so if anything you should keep the stock compression or raise it. I run 6.2 compression with the 6.2 ATT in the 2500 burb and get 15 MPG in town.
4. diamond precups or just enlarging the ones that it has
ABSOLUTELY Get Diamond Precups!!! Any other precup will limit the amount of air and power your engine can use. Of course my High MPG burb has 6.2 NA military precups, but, we are limited to 17 PSI of boost no matter what we do with fuel or timing.
5. Head studs
Use locktight or other sealer on them. Good idea to use them.
6. ATT turbo
You want power and economy...
7. Intercooler, I have one that is already modified to fit from when the cummins was going in
Cost? IMO it isn't worth the trouble as air temps with the ATT are low enough - 270 F peak on mine.
8. 2.5" crossover and either a 3 or 4" downpipe. Problem here is getting the exhaust to clear my t-case since the truck is a passenger side drop t-case.
Crosover isn't critical, but downpipe and exhaust go as big as you can.
9. high flow waterpump
Check
10. Dmax fan
Check
11. Dual t-stat housing
Waste of money and will cause clearance issues with the throttle cable. A single t-stat with a HO pump and above fan does well. If it runs hot get a lower t-stat and lower temp fan clutch.


I would go with custom headers as the stock exhaust is known to be restrictive. But stock will work with the noted issues.

Miles on injectors?
Feed the beast mod?

 

[WarWagon]

Oh, and the 1987 body style doesn't have the radiator airflow problems the newer, say 1993, body styles have. So cooling and big fans are not as critical. Thus another reason you could skip most cooling mods. HO pump and big fans do use MPG's... But they are nice to have when you need it.

 

[red]

Well oil pan is off, to my untrained eyes I have not noticed any cracks on the mains but I'll be posting pics soon as i can find my memory card reader.

So far I have:
-pulled pan to inspect the mains
-pulled timing cover and removed water pump
-removed turbo (will be selling, I'll try to get more info on it. shaft has minimal play feels almost new
-both exhaust manifolds (easiest ones I have ever pulled, didnt fight me at all)
-upper intake manifold. shot myself in the foot here when i was removing it
-lower intake manifold, gonna need a new one of these thanks to forgetting a bolt that was mounted to the upper intake.

The injection pump is a db2-4911 model!!!! currently it has more wires on it than I expected for a mechanical pump, maybe cruise control related? There is a tps on the side of it which accounts for most of the wires (3 of them), then there are 2 more wires. 1 looks like it goes to a cylinder up by the throttle cable bracket, kill wire i'm guessing. the last wire is the only one i'm not sure of, connects towards the top of the injection pump. I want as few wires floating around as possible, so I really want to know what that last wire is for. the TPS will be coming off.

On the top of the block in the intake valley the numbers 5991 are there.

To run an intercooler will only cost me plumbing, my core support was already modified to fit the intercooler when i was doing the cummins setup.

Injectors have unknown miles, are they difficult to rebuild?

Feed the beast mod will be done.

Good to know on the cooling issue. Helps that I have a 4 core radiator with no built in oil cooler.

Would the motor be happy with the stock 21 compression and running about 15-20lbs of boost with the ATT? Thats my reason for thinking of lowering the compression but if its not needed thats less labor and expense.


I'll keep searching for my memory card reader so I can post up the pics.

 

[red]

woohoo now I can upload my pics again!


Heres the 5991 mark that i mentioned

my screw up with the lower manifold

glow plug relay, might still be useable

This is that wire that I'm not sure what it does, any ideas?

Motor when I set it down last night

 

[NVW]

Your block is a 599, what appears to be a 1 is just random dots.

 

[deejaaa]

well it looks like you have the early block. still a good block but not the latest.

 

[red]

Would have been nice to be a new generation block but the 599 is one of the stronger castings isnt it?

1 other wire thats all by its lonesome and hasnt been connected in a long time, from a crank position sensor maybe?

 

[DieselCash]

The 92-93 6.5TD does not have a crank position sensor. There is no computer to read the any input from one either.

 

[DieselCash]

On your pump wire question.

The lower wires is the HPCA cold start wire.

The upper wire is the Fuel Shutoff solenoid.

 

[turbonator]

As was stated, your block is a 599, the wires on the IP are all needed (other than TPS) for starting and running. The larger pink wire is the shut-off solenoid, and the two green wires are for the high idle (at linkage ) and the cold advance. They are thermostatically controlled by a switch in the back pass side of head.

We would suggest head studs , girdle, and main studs. We have run two motors now with our 5 pin girdle, and have not had any problems, even opened one up after 5000km to inspect. Will be installing one on a third motor now (3" of blockfiller also), and will have main-line honed if needed, Preliminary verifications indicate that again no block distortion from girdle or blockfiller.

Depending on the efficiency of the turbo you chose (we presently are running Holsets), should keep it 15psi or lower if not lowering compression. As an aid to eliminate head gasket failure, we have began to fire-ring all our blocks. The Diamond pre-cups are necessary for turbo'd motors, as the n/a pre-cups are a restriction to the swirl in the Ricardo chamber. We totally cracked a set of n/a cups that we boosted up to 30 psi with.

Good luck with your build, our 3500 eats comparably sized trucks with the big-block in them. We run a mech .310" as you will be running (maxed with minor mods).

Your greasy wire is for a crank sensor, used with the 599 block with the DS4 pump only in 1994. You do not need it for a mechanical pump.

 

[WarWagon]

Wipe the oil off the sides of the main webs. Cracks will have oil leak out of them and be as plain as day left overnight.

Looks like you have a 1994+ timing cover. So you have what was once a electronic DS4 engine with a mechanical IP put on it. Was a junkyard swap out or the like. This is why you have the unneeded CPS and related wires. Be careful with the oil filter adapter as the design changed over the years - so when you replace the o-rings on it make sure they are the proper ones or copper gasket on some years... Or maybe they just changed the timing cover?

 

[deejaaa]

the oil looks gray, or is it just the flash? the 2nd and 3rd pics were fuzzy so detail was washed out.
nice pics BTW. i like using an image host also. get to really see the detail.

 

[red]

Oil is the usual black, either the flash or the sunlight messed with those pics. I'm not sure how that camera still takes as good of pics as it does considering what it went through in Iraq and about 2 years on the demolition range haha.

WarWagon with the oil filter adapter is there an easy way to tell by looking at it? Got the oil wiped away so should know in the mornin.

Turbonator if you dont mind me asking where do you get your fire rings at and what all is required to install them? I like your design for a stud girdle, debating on installing one.

This is the truck that has gone through a few motor changes lately

 

[WarWagon]

My memory is fuzzy on this for the 93 and 95. Best I recall and may be backwards: Some have a copper washer under the bolt and 1 o ring for the bolt in the adapter. Others have 2 o rings on the bolt and no copper washer. The bolt o rings are different diameter and quantity and where I had trouble getting the right parts. I think the main block o ring is the same. So keep in mind differences or bring the bolt and adapter in to the dealer and go through 6.5 years till you match parts.

 

[turbonator]

We purchased a Groove-o-matic, upon suggestion from "6.2 turbo". The actual ring is a copper wire seated into the groove in the deck surface. We left the wire .015" above to hold the fire-ring of the actual head gasket in place. We have used it now with MLS gaskets and Felpro, both over-thickness. The next we will try it with Victor Reinz standard thickness head gasket. Seems to work well, it is a simple method to eliminate potential pressure loss and minimize machining of the decks to repair the typical deck burn areas.

The first girdle we used, was just with modified (new) head blots, now we have sourced a full set of ARP studs for the bottom end. As of yet, we have never dropped a crank, and after working the first motor with the girdle in a C-5000, pulling our trailer and machine (30,000lbs in mountains), we had no cracks, no abnormal bearing wear, and no off-center bore wear. These were all things that we were told originally would happen with a girdle. The motor in the "swbchevy @ 304rwhp" has been running a 3 pin girdle from the beginning, and it is going on 4 years now. Extreme service.....

 

[deejaaa]

................first girdle we used, was just with modified (new) head blots, now we have sourced a full set of ARP studs for the bottom end. ...never dropped a crank, and after working the first motor with the girdle in a C-5000, pulling our trailer and machine...no cracks, no abnormal bearing wear, and no off-center bore wear. ... motor in the "swbchevy @ 304rwhp" has been running a 3 pin girdle from the beginning, and it is going on 4 years now. Extreme service.....

now THAT is impressive!

 

[Chevy3500]

The best way to check for cracks is tear it to a bare block, then take it to the machine shop and have them magna flux it.

 

[red]

motor has sat for over 24 hours and didnt notice any cracks so looks like I might be lucky. I turned the motor right side up and started pulling the heads. I have the valve cover, rockers, tstat housing and alt bracket removed from the head along with all of the bolts that I can see from the top. Head wont budge when I try to remove it, does the gasket tend to make it that difficult to remove or am I missing a bolt somewhere?

Also been looking at other things to upgrade/replace with the motor apart. Is there any reason to go away from a timing chain to a gear drive system for the cam/crank? Does anyone make a cam for the 6.5 or is the stock cam the better option?