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What did you do with your GMT400 today...or yesterday....

Will L. said:
Man that just scares me being in the rock/ brush smash zone. I prefer behind bumper or up near radiator or something like that.
Click to expand...

It goes behind the plate. I do a lot of off-roading and I’d be majorly screwing up to hit something that would bash that high.
 
Got back last night from another fun trip to Texas. Great people there and met a few more...Truck, oh yes, truck...
Came home to Boxes for the truck and Burb which I unwrapped.
1. PMD retune for the the Truck. Had to donate mine for the Burb and have been switching them between. Will install and drive it later today. Too early to wake the neighbors yet.
2. 1st of two parts of the Heath SuperCool kit. Waterpump. Guess the impeller mod guy Heath contracted is catching up on the orders.
3. 2nd Half consisting of the D-Max Fan, Clutch and T-Stats. Plus stickers...gotta have the stickers to make it work right. Looking forward to the install this week.
 
Paveltolz said:
Got back last night from another fun trip to Texas. Great people there and met a few more...Truck, oh yes, truck...
Came home to Boxes for the truck and Burb which I unwrapped.
1. PMD retune for the the Truck. Had to donate mine for the Burb and have been switching them between. Will install and drive it later today. Too early to wake the neighbors yet.
2. 1st of two parts of the Heath SuperCool kit. Waterpump. Guess the impeller mod guy Heath contracted is catching up on the orders.
3. 2nd Half consisting of the D-Max Fan, Clutch and T-Stats. Plus stickers...gotta have the stickers to make it work right. Looking forward to the install this week.
Click to expand...

I checked the pricing on the Heath SuperCool kit and it's ridiculously high. Let me know how it works as wee need to address the overheats on my son's '94. The HO Pump and Dmax fan work mighty fine with the ATT on my '99.
 
Super Cool kits have worked wonderfully on my Chevy (I put a new one on with the new motor in 2012). Previous to that, the Chevy would run up to 210+ on the slightest grades under it's own weight during the summer. Afterwards, never saw anything like that again. When I ran the Winch Bumper it only got a bit above 200 on the way up the hill at the CA/NV border heading towards Baker. I attributed that to the blockage of air through the stake given the lack of 'nostrils' in the bumper and that bumper is the one now on your son's 94.
My understanding is that the newer kits have an improved impeller design on the waterpump. Looking forward to no more weeping/leaking and 200ish hill climbs with the Burb.

I noticed a 4th box from Monitronics this morning. Much smaller. Anyway, that one held a new Turn Signal Relay EF29L (L for LED bulbs). Ordered it to cure the rapid flashing issue and not have to add the resistors by taping into the existing wires. Pull the old OEM EF29 and plug in the new one. Works perfect.
 
Paveltolz said:
Super Cool kits have worked wonderfully on my Chevy (I put a new one on with the new motor in 2012). Previous to that, the Chevy would run up to 210+ on the slightest grades under it's own weight during the summer. Afterwards, never saw anything like that again. When I ran the Winch Bumper it only got a bit above 200 on the way up the hill at the CA/NV border heading towards Baker. I attributed that to the blockage of air through the stake given the lack of 'nostrils' in the bumper and that bumper is the one now on your son's 94.
My understanding is that the newer kits have an improved impeller design on the waterpump. Looking forward to no more weeping/leaking and 200ish hill climbs with the Burb.

I noticed a 4th box from Monitronics this morning. Much smaller. Anyway, that one held a new Turn Signal Relay EF29L (L for LED bulbs). Ordered it to cure the rapid flashing issue and not have to add the resistors by taping into the existing wires. Pull the old OEM EF29 and plug in the new one. Works perfect.
Click to expand...

Supply side economics at work ^^^^^^ MAGA!
 
At what point did he start doing a custom impeller on the pump?

My neighbor bought the whole kit from him around 1 year ago for his burb and asked me to help install. Compared that pump to the test ran $20 take off ones I bought from Peninsular and it looked exactly the same. He even put caliper on impeller trying to tell me he though I had to have a low flow version- he was confused on info about old 4 bolt style vs 4 bolt ho pumps. We thought maybe different impeller grooves, but we couldn’t see a difference. I remember it was cast piece just like the factory one, and thought if it was a custom impeller, it would probably be a milled piece.

Did they do flow testing to see their new impeller says balanced? Hows about volume- are they pushing over 130gpm?
 
Will L. said:
At what point did he start doing a custom impeller on the pump?
My neighbor bought the whole kit from him around 1 year ago for his burb and asked me to help install. Compared that pump to the test ran $20 take off ones I bought from Peninsular and it looked exactly the same. He even put caliper on impeller trying to tell me he though I had to have a low flow version- he was confused on info about old 4 bolt style vs 4 bolt ho pumps. We thought maybe different impeller grooves, but we couldn’t see a difference. I remember it was cast piece just like the factory one, and thought if it was a custom impeller, it would probably be a milled piece.

Did they do flow testing to see their new impeller says balanced? Hows about volume- are they pushing over 130gpm?
Click to expand...
Who was confused, the neighbor?
Bill said it was a recent change when they started the impeller design thing and that my truck wouldn't have it...too old (2012). It was news to me and I'm pretty current about his goings on since I'm always talking with him about other stuff as well as trucks. I admit I haven't talked heating and cooling with him for a long time though since I haven't had any issues.
As for the 130 gph, from what I can tell, that number first started on another forum some time ago (I think it was the Diesel Page) at it has taken on a life of its own. But, does anyone know a reliable entity who has done a flow test on the thing to establish quantifiable numbers? Bill doesn't discuss numbers that high, rather, closer to 95gpm.
I just know the set up works which is fine by me.
 
Yes, the neighbor was confused as to the old style pumps between regular flow and high output.
The real spec numbers from GM are
97 GPM for the original 4 bolt pumps on v belt, and first serpentine belt pumps.
Then GM released the HO 4 bolt pump with spec of 127GPM.

Then the redesign of the pump which used the spinon was listed at 127 by GM also.

However in the AM General vs GM lawsuit which resulted in the creation of GEP, they (AM General) actually showed the spinon produced 130 gpm. Gm engineer stated in court it was still considered 127, and that the extra flow was byproduct of the easier flow through and less restriction. And that the balance flow is what eliminates the problem. So when GEP started producing the Optimizer, they were still not allowed to use the spinon balance flow design of GM until they released the sale of optimizers to the public and GM was released of their contract to HAVE TO build the 6.5. This was a sticking point because they showed that at 140 gpm it was too great and caused cavitation points on cylinder jackets and that was why their first balanced flow redesign they tried to get AM General to accept was declined. They already done their testing by that time after thousands of wasted hmmwv engines. So GM had to pay back a loss of 1/2 million bucks for that 140 gpm pump to AM General amongst some of their losses in the suits.

So when you see someone refering to a 127 or 130 gpm, understand the number is basically the same and not yet another redesign of GM’s pump. 95gpm is a number I have never heard of, possibly typo of 97?

Once all the time limits expired on GM 4 bolt waterpump warranties, Then GEP started it’s use of the spinon for hmmwvs.

So anyways, the balanced flow waterpump- which is the spinon waterpump style- has been going since then.
I would NEVER buy a reman waterpump after the fiasco of HO 4 bolts being rebuilt with 97 impellers. That just shows me some clown company could rebuild a spinon waterpump with an incorrect impeller. Remember, the impeller in the 127 HO pump is not the same as the 127 spinon balanced flow.

The reason the spinon waterpump corrects the issue is a redesign of the chambers in the body, and a complete redesign of the impeller.

So if Bill had a special impeller, different from GM’s last design, (which is in use now on all optimizers, 6500 and 6500-p400 option,that come as longblocks unless ordered for v belt use...

I wonder what he did to improve on it. Because the “balance flow” is within 1% of balanced. And at an actual 130 gpm and problems at 140, less than a 7% increase in flow? And if so did they do the turbulence testing?

He is always working on improvements and should be commended for it. But much like the rear head cooling kits he (amongst many others) used to sell- they proved to not just be not helping but damaging. As I mentioned many times before, I appreciate him quitting selling them (too many other places still after a quick buck still do). My concern would be that another attempt to make more improvement could cause issues.

If not and he found info showing lets say 137 gpm is the peak performance without issues, I would sure like to know it is available, for myself and others out there. Especially since other Hummers are being done with multiple radiators, and I may end up with that result still.

Or is it kinda like the camshaft thing where it sounds like it has great potential to smooth out power feeding a sidemount turbo, yet would be obvious counter productive on a centermount like hummers/vans. But he won’t share enough details to allow customers to make an informed decision before purchase. Buy it and see just doesn’t work out with these engines sometimes.

I get it he risks someone copying the idea if the extra flow from 130- but much like Kennedy’s fan clutch- anyone that learns much about the cooling system knows faster and higher percentage of lockup works better, and since Hayden and the other supplier before then(forgot name) makes and sells them only to him for a just under 10% increase in fan speed-not sure that many will bother with milling or casting an impeller to compete with limited sales. Someone would have to spend thousands to knock off his design, unless they (or he) just shot from the hip- which is just stupid knowing all the history of problems in these systems.
 
Will L. said:
Yes, the neighbor was confused as to the old style pumps between regular flow and high output.
The real spec numbers from GM are
97 GPM for the original 4 bolt pumps on v belt, and first serpentine belt pumps.
Then GM released the HO 4 bolt pump with spec of 127GPM.

Then the redesign of the pump which used the spinon was listed at 127 by GM also.

However in the AM General vs GM lawsuit which resulted in the creation of GEP, they (AM General) actually showed the spinon produced 130 gpm. Gm engineer stated in court it was still considered 127, and that the extra flow was byproduct of the easier flow through and less restriction. And that the balance flow is what eliminates the problem. So when GEP started producing the Optimizer, they were still not allowed to use the spinon balance flow design of GM until they released the sale of optimizers to the public and GM was released of their contract to HAVE TO build the 6.5. This was a sticking point because they showed that at 140 gpm it was too great and caused cavitation points on cylinder jackets and that was why their first balanced flow redesign they tried to get AM General to accept was declined. They already done their testing by that time after thousands of wasted hmmwv engines. So GM had to pay back a loss of 1/2 million bucks for that 140 gpm pump to AM General amongst some of their losses in the suits.

So when you see someone refering to a 127 or 130 gpm, understand the number is basically the same and not yet another redesign of GM’s pump. 95gpm is a number I have never heard of, possibly typo of 97?

Once all the time limits expired on GM 4 bolt waterpump warranties, Then GEP started it’s use of the spinon for hmmwvs.

So anyways, the balanced flow waterpump- which is the spinon waterpump style- has been going since then.
I would NEVER buy a reman waterpump after the fiasco of HO 4 bolts being rebuilt with 97 impellers. That just shows me some clown company could rebuild a spinon waterpump with an incorrect impeller. Remember, the impeller in the 127 HO pump is not the same as the 127 spinon balanced flow.

The reason the spinon waterpump corrects the issue is a redesign of the chambers in the body, and a complete redesign of the impeller.

So if Bill had a special impeller, different from GM’s last design, (which is in use now on all optimizers, 6500 and 6500-p400 option,that come as longblocks unless ordered for v belt use...

I wonder what he did to improve on it. Because the “balance flow” is within 1% of balanced. And at an actual 130 gpm and problems at 140, less than a 7% increase in flow? And if so did they do the turbulence testing?

He is always working on improvements and should be commended for it. But much like the rear head cooling kits he (amongst many others) used to sell- they proved to not just be not helping but damaging. As I mentioned many times before, I appreciate him quitting selling them (too many other places still after a quick buck still do). My concern would be that another attempt to make more improvement could cause issues.

If not and he found info showing lets say 137 gpm is the peak performance without issues, I would sure like to know it is available, for myself and others out there. Especially since other Hummers are being done with multiple radiators, and I may end up with that result still.

Or is it kinda like the camshaft thing where it sounds like it has great potential to smooth out power feeding a sidemount turbo, yet would be obvious counter productive on a centermount like hummers/vans. But he won’t share enough details to allow customers to make an informed decision before purchase. Buy it and see just doesn’t work out with these engines sometimes.

I get it he risks someone copying the idea if the extra flow from 130- but much like Kennedy’s fan clutch- anyone that learns much about the cooling system knows faster and higher percentage of lockup works better, and since Hayden and the other supplier before then(forgot name) makes and sells them only to him for a just under 10% increase in fan speed-not sure that many will bother with milling or casting an impeller to compete with limited sales. Someone would have to spend thousands to knock off his design, unless they (or he) just shot from the hip- which is just stupid knowing all the history of problems in these systems.
Click to expand...
Nice write up, thanks. I'd like to see those documents from GM are published/posted on line, I'll try google search later. In the meantime, it would make a good post in the Parts Reference Stickies.

As to what I did with my GM 6.5 today, took the Grandkids out for Ice Cream with it. Fund day.
 
Any day with ice cream involved is a good day- haha.

Search the lawsuits - thats where I remember reading most of the info. I had people send me links, wish that old computer didn’t die, or I understood how to back up hard drives back then.
 
Will L. said:
Any day with ice cream involved is a good day- haha.

Search the lawsuits - thats where I remember reading most of the info. I had people send me links, wish that old computer didn’t die, or I understood how to back up hard drives back then.
Click to expand...
I love ice cream, a heaping bowl every evening an hour or so before bedtime. Beginning of summer I started becoming lactose intolerant. The wifey she brought Me home some frozen yogurt, just not the same. This evening I found out there is a pill for lactose intolerance. I`m going for that. LOL
I got the new vacuum pump installed and now have some pretty nice boost.
 
99 Burb. Started on the water pump replacement. Was a wrestling match with the Fan refusing to come unscrewed. Took it all out as a single unit. Some dexterity required to get at the lower bolts and one behind the bypass hose. Bypass hose fought back as well as the stupid radiator drain..plugged with gack. Glad I have a spare radiator cause it's going to get swapped in tomorrow too. New hoses won't be in until 11 am though. Doubt I'll have it all back together in time to drive it to Vegas.

Was going to to Harmonic Balancer and Pulley but they're both in great shape so, I'll do them another time.

Learning that the wiring for GPs goes down the front of the motor on the passenger side on this one vs. down the back for the 96 Chevy. But, that's another project for when the Turbo, injectors, glow plugs and inner fender get swapped out...next week maybe.
 
Paveltolz said:
99 Burb. Started on the water pump replacement. Was a wrestling match with the Fan refusing to come unscrewed. Took it all out as a single unit. Some dexterity required to get at the lower bolts and one behind the bypass hose. Bypass hose fought back as well as the stupid radiator drain..plugged with gack. Glad I have a spare radiator cause it's going to get swapped in tomorrow too. New hoses won't be in until 11 am though. Doubt I'll have it all back together in time to drive it to Vegas.

Was going to to Harmonic Balancer and Pulley but they're both in great shape so, I'll do them another time.

Learning that the wiring for GPs goes down the front of the motor on the passenger side on this one vs. down the back for the 96 Chevy. But, that's another project for when the Turbo, injectors, glow plugs and inner fender get swapped out...next week maybe.
Click to expand...

You going any further than Vegas?

Sunday I’m off to NY for two weeks.
 
Installed the new boost control solenoid.
Got an exchange from NAPA for the one that failed, at least I hope that is what the problem is.
 
Replaced the block water heater and power cord. Previous owner had cut the plug and unplugged the cord at the heater. One of the power input pins was missing so the thing was obviously inop. He put a heater on the oil pan but its glued and covered in some sort of fiberglass heat patch. It'll probably work just as well but, 'Since I Am In There' with the water pump replacement (along with the other stuff I'm trying to do 'while I'm in there' I put in a 1000Watt heater. I'm apparently not as bendable anymore cause it took a lot longer than I'd hoped it would. Good thing the old unit wasn't as corroded as I had feared. Once I got the angles figured out and the screwdriver to bite, it went pretty quick.
NEXT: I was going to replace the glow plugs and Injectors but, on inspection, the glows are the only thing shiny on the motor so I'll just do the harness. Injectors will have to wait as I passed them off to AKDiesel last night to set the pop pressures. Besides, the injectors in there now are the next to newest thing I see after the Glow Plugs and, the return hoses are the the clamp-less design. Definately not that old when looking at the rust on the exhaust manifolds and heads.
 
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