• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

New Optimizer Long Block

JohnShead

JohnShead

Member
Messages
72
Reaction score
63
Location
Kingsport, TN
So, after getting my truck running with an AC Delco rebuilt IP it was running beautifully pulling our 6800 lb travel trailer, lots of issues with cooling but this pump made it run better than I ever remember (I was running on a bad IP for quite a while). Then I fogot to put the cap on after topping off the coolant for the 1600 mile trip home from our daughter's wedding. Climbing out of Custer, SD it blew something and boiled out all of its coolant. It sat for couple of years in the garage until I could get around to pulling the motor and tearing it down, and when I did the damage repair, with mods, would cost nearly as much as a brand new Optimizer 6500 from Leroy. So I bought the long block, I picked it up last month in Franklin, OH. I've transplanted my Phazer Gears and FluidDamper to the new motor. I got a billet steel flexplate and assorted ARP bolt kits from QuadstarTuning.
The problem is, I still want the mods, one of which is flashing removed, which requires a complete disassembly. Now since we're here why not put in gapless rings, main studs (not sure about girdles), head studs, MLM head gaskets (one thickness over stock for a little less compression), roller rockers, and I really want to have it balanced. I've read about it and am pretty confident I could do the reciprocating parts but the crankshaft is definitely not DIY so I need to find a shop for that.

Am I crazy or should I just drop it in the way it is?
 
That is exactly the decision your wallet has to make.
To me- these engines are expensive enough and have enough problems from factory that it only makes sense to tear apart and do it. You will spend another $1,000 -3,000 depending how much you do but the engine now lasts a lot longer…most likely. There are some that run 300,000 miles without being touched but most dont.

Balance, gapless, flashing removal are no brainers to me. The machine shop does the balancing- not you.
the TSP girdle is also worth the insurance money imo. Changing the other mains out for studs is only a bit more and all in the name of protecting main webs and crank is easily justified. Overheating and lower end failure are the two weak points.

Head studs is only based on what are you doing with turbo & boost. Running mostly stock I say stay with head bolts and Mahle or Felpro gaskets. The unique issues we have with headstuds means don’t do it unless you need to.

Roller rockers are a definite improvement but don’t pay for themselves. Replace the plastic rocker pins with bolt& nut is worth the few bucks and time unless you are 100% that at 150,000 miles max you replace valve covers& plastic pins. Oh yeah- replacing the valve covers is usually worth it because getting used ones to seal takes some practice.

If you are using the roller rockers for the increased lift ratio- then it’s more to consider if worth the cost and they eliminate the plastic pins too. Personally I went to TSP 18:1 pistons that has the valve reliefs and had Leroy get me a set if 1.7:1 roller rocker arms to go on my p400 heads So it will flow a lot more. I wish I could have TSP do the cnc porting but had to let go of some things.

Your damage was from loss of coolant and a temperature gauge will read last known value then slowly show cooler while the coolant is all gone. I have dealt with this too many times. I am going to add a LOW COOLANT SENSOR in my surge tank (aka overflow tank for older rigs). On the same scenario but loosing engine oil, I am adding a LOW OIL SENSOR into my oil pan while off.
These will trigger a relay that feeds a warning buzzer and bright flashing LED on my dash - I decided to stop short of a cattle prod to my leg and laser beams into my eyeball, but just barely decided that too far. A low oil pressure sensor and a high coolant temp sensor can get added into the same relay and complete the safety warning items.
All of which I am sure is not cheap but I am not loosing this engine to those possible hiccups- so insurance money well spent imo.
 
JohnShead said:
it was running beautifully pulling our 6800 lb travel trailer
Click to expand...

Get a better turbo than the OEM GM Asthma Attack® turbo. It will pay for itself in improved MPG towing. Less heat that can't get out the exhaust from GM's extreme backpressure with the turbo also gives you more power when the fan isn't screaming.

You should contact @Twisted Steel Performance about coatings to keep heat out of the cooling system. IMO his work and products are second to none. This includes many coatings in the engine as well as condensers and radiators.
 
JohnShead said:
Then I fogot to put the cap on after topping off the coolant for the 1600 mile trip home from our daughter's wedding.
Click to expand...

@Will L. Maybe the OP can clarify how much coolant it was using. "Adding" coolant means it was either going way over the ring ruining 210F and popping the cap open OR already had a head crack/gasket leak eating coolant.

Keep it at 210F max and consider 220F an emergency pull it over.

Lose a hose or the block heater falls out and the sludged up low coolant sensor is USELESS ... takes too much time to trigger the light. The Moon gauges of a 1988 we had are not well placed to see the gauge peg on hot when the block heater blew out of the engine. Some vehicles even omit a useful engine temp gauge...
 
I really wanted to do some of those mods before installing the new Optimizer into My truck.
I even have the timing gear set waiting on the work bench but decided to not remove any components from the new engine so I would not be taking a chance of developing an oil or coolant leak.
I figure this new engine will run at least 200,000 miles and I doubt that in the next 25 or so years I have left on this earth, I’ll never stack that many miles.
If ever I do make it to 100,000 to 125,000 miles then that timing gear set will get installed at that time.
Besides, I drove My CC too high for My comfort zone just getting the engine and the up rated components that I did poke into it.
 
I was faced with a similar challenge a couple years back. You can read about the saga from my signature line if you want. Somewhere along the way, @Twisted Steel Performance commented that the engine I asked him to work on was the worst he had seen in terms of balance and it was essentially "new" with 1400 miles on it. It made sense to me to have it torn down and gone through.
 
I'll be addressing my cooling issues too but at this stage I'm just trying to decide if I should tear apart this motor and dump a lot more $$$ into it. It seems I should though from all I've been reading, currently SnowDrift's 22 page saga. It took about a quart of coolant to top it off after the 1600 mile trip to the wedding, I did hit 220 many times but I didn't know that was such a no no then. My EGT was in the yellow arc when that happened too so I did back off to get it back down. I also didn't know at the time but I had a worn out fan clutch, it's been 2 1/2 years since that trip so memory is muddled now, but I think I was hearing the fan come on at around 210. It was a KD special calibration clutch but it was over 10 years old and I have learned here the these clutches are only good for 5 years. I had an A-Team turbo in the past but it broke and I put my GM4 back on to get it running again. I'm planning on a Super54 from Quadstar this time. Would replacing my 3.5" exhaust with a 4" make much difference?
 
The best way to look at the added cost to make certain mods vs the cost of said mods is, how long would you like to keep the truck, is the body, frame, etc worth keeping to you. If you hope to go to a newer truck down the road you may feel just keeping it running is all you need... Some of us have a very nice truck that's paid for and we like it so it's worth spending money... That's your decision alone ..
 
My question on these new optimizer engines, say if one purchased from one of the vendors here like Quadstar. would tearing into it t do the upgrades or even opening it up for some of the simple tings void any warranty that it comes with?
 
That scares me from ordering! new engine (not that it would happen) ordered to the doorstep with some sort of defect only to find out once it's installed and attempted to run.
 
Twisted Steel Performance said:
One of the reasons I have a run stand, I at least prove they run and don't leak, and I can run them as long as I want to.
Click to expand...
If I was looking at replacing an engine in a vehicle that justified the investment, sending it to Chris is the only route I would consider at this time.

Otherwise I've always bought new crate parts or found a running donor vehicle.
 
My new optimizer made it 70,000 miles untouched. Then spun a cam bearing from the flashing coming free. It ruined the bearing and the cam obviously. I stopped it in time before the spinning bearing ruined the block.

Now here’s the thing- where is your oil pressure gauge attached?
Center of the valley right? Half way down the camshaft right? The bearing that spun is after the sensor. On my engine the oil pressure gauge was at the rear of the engine- opposite of where side mounted turbo oil supply is at. So I had a couple bearings after my sensor that still restricted flow as they should before the spun bearing. So my oil pressure drop was only a 10 psi drop from where it was the day before, but still way high that is considered good oil pressure.

Only because I constantly note the gauges And noticed the difference when I heard a funny sound and a momentary blip in power did I take it seriously. Knowing that it is usually the very last (front) cam bearing that gets damaged, and since I was planning on adding my centermount turbo soon anyways which required me removing the engine the way I was doing it- I removed the cam and saw the problem. It would have kelt running and had oil pressure for maybe another 1,000 miles then ruined the entire engine- block crank, etc.

I knew when I put it in the smarter choice would be disassemble, inspect and reassemble even if I made no alterations. NO WARRANTY. But I justified it by saying “GEP builds these for war fairing equipment- millions and millions of new engines are made every year- this should be fine.”
No. DOGE should be inspecting AM General- specifically GEP because the failure rate of the 6.5 is absolutely horrendous. They are slapping these engines together by standards thought ok in the 1970’s except the absolute worst unbalanced lower rotating assembly any one at any machine shop has ever heard of. Why? THERE IS NO FACTORY SPECIFICATION AS TO BALANCE!! They just slap together and figure it’s ok. Meanwhile modern engines have a specification because they learned it makes a difference in not just longevity but efficiency. Better mpg and emissions.

If a person doesn’t want to upgrade rings, coated bearings, or doesn’t even care to get the balance closer by diy methods- (if broke and don’t know how, ask) then fine.
But buying an $8,500 engine that seem to have a chance of catastrophic failure in under 100,000 miles… spend another few hundred dollars and ensure it will live a lot longer life.
Disassemble. Throw away the gaskets and head bolts & main bolts. Sit down with a $20 die grinder and $20 bit (if you dont already have them) to remove all the flashing. Maybe 3 hours if you never did it before and have the worst cast one ever. Use $5 in plastigauge and check clearances if you dont have the better measuring tools. 4 hours.
A $10 scale from amazon will let you use same die grinder to get rods and pistons amazingly close to equal. Yes the crank being done is a big improvement but rods & pistons are half the battle and a guy can diy them close in a single day. The new gaskets and bolts are not expensive. Head bolts-$50, head gaskets-$50, main bolts I haven’t priced lately but you get the idea. This will cost time and money- but not like it requires 2 months and $1,500 additional.

Adding in more money for further improvements is case by case. Mine is over the top but I’m an old picky guy that has always wanted one done this way. If I could have afforded it, it would have been done long ago but other things take economic precedence.

Idk- maybe someone here is an insurance statistics person and can show the math how it’s only worth an additional $127.31 on top of an $8k engine to be worth the risk.
But my experience says do it.
I get hassles for “the sky is falling” but look where I am. New optimizer- spun cam bearing. Fix that and put together adding a factory designed turbo and buying “save” $25 buy getting glow plugs online instead of napa or dealership = destroyed piston.
I grew up and lived most of my life in Vegas. I understand odds. I see it as newr crazy to not do this - that why I tell everyone to do it.

If you had it as a factory option- $8k for the generic mass production engine or an additional 10% cost for a hand built one that will run smoother and improve lifespan & mpg - would you do it?
 
You must log in or register to reply here.
Back
Top