Extra Cooling for rear of engine

[Shadrach]

I thought about adding extra cooling to the back of the block. I have the Cummins part for doing it on an 02 or older block but the HPCR block is different so it won't work. What do you suggest? The truck will be used for RV towing. Thanks in advance. Shadrach

 

[Diesel Gunner]

OK, I will bite. I was not aware that there was a part to cool the back of the block.



What is it? PM me if you like.

 

[CDonaldson]

I installed the Opie Cooling System Bypass, do a search here, I'm sure there HAS to be a thread. I am very pleased with the Opie's performance, my towing temps ARE lower.





CD

 

[CoastyAV8R]

You guys have to tell the rest of us how you cool the back of the block...

 

[TRowatt]

From what i understand its a kit that goes into a port on the back of the block that then returns the coolant back to the radiator. So instead of a dead end system it becomes a loop system letting the back of the block cool better.

 

[NavyDood]

Uhhh... isn't that what the coolant bypass does?

 

[cerberusiam]

The rear 2 cylinders have always had a problem cooling when you push the limits of the cooling system. It has to do with the internal casting and a choke point that does not allow the return flow to be as good as the rest of the block.



The problem with the 3rd gens is when you push the power it creates too much internal pressure in the back of the block and blows freeze plugs. It will on the earlier blocks also but it takes more to get to the point where it happens.



The kits like the Opie bypass install and alternate route from the back 2 cylinders controlled by a pressure relief valve so it will relieve the pressure and not blow freeze plugs. The original Cummins kit was evidently there to help with cooling in certain circumstances where the rear cylinders were seeing issues.



There is not a lot of correlation whether it helps or not and at what point it is needed, but, anything that will help with heat soak on 5 and 6 cylinders has to be a positive. A bypass that is regulated by pressure is probably not ever going to do anything as it will never reach the critical point. A metered bypass will work all the time and should help some.



Is it needed? Probably not at the levels we run these trucks towing. Is it a bad idea? Nope.

 

[Shadrach]

I'm not familiar with " Opie " Anyone got a link Thanks Shadrach

 

[cerberusiam]

I'm not familiar with " Opie " Anyone got a link Thanks Shadrach

Try Google, it comes right up.



Welcome to Intelligent Engineering, Inc - Manufacturer of the strongest high performance diesel parts in the world!

 

[NavyDood]

So why the added expense for the relief valve of the bypass kits? If there is a choke point back there then why not just do the bypass without the relief valve? Does it disrupt proper cooling back on cylinders 5 and 6 if it didn't have the relief valve?

 

[TRowatt]

Navy check out wicked diesels site as well they have a coolant bypass system. not sure if it uses a pressure relief or not but it looks like a nice system.

 

[cerberusiam]

So why the added expense for the relief valve of the bypass kits? If there is a choke point back there then why not just do the bypass without the relief valve? Does it disrupt proper cooling back on cylinders 5 and 6 if it didn't have the relief valve?

Thats the exact question that is hard to quantify.



If all is needed is a metered orfice to provide some restriction, why a pressure valve?



Does one really NEED extra cooling or just a pressure bypass?



Considering the more heat one holds in the engine the better the efficiency isn't a bypass self defeating except when it relieves pressure?



Exactly WHERE is the point at which the bypass provides its worth, in either scenario?

 

[jelag]

We have an 04 now with close to 300K miles towing a 20K lb trailer around the west coast, Spokane, I-5 to San Diego, Phoenix, Las Vegas, Billings and back to Spokane in all climates... . we've not had a problem and will run this truck until it gets to 500K miles before we trade it... . by than the body and truck will be well worn... .

We've done this on a lot of trucks, can't imagine they aren't built for it... .

 

[Shadrach]

Try Google, it comes right up.



Welcome to Intelligent Engineering, Inc - Manufacturer of the strongest high performance diesel parts in the world!

I tried that but couldn't find anything on their site about cooling bypass Shadrach

 

[CDonaldson]

There is a good thread over on Competition Diesel Forums Opie/Intelligent Engineering is a vendor there, the thread is in the vendors section. Some install pics as well. Full explination regarding the issues with the rear cyl temps, etc.



The rear cyl meltdowns and blown rear freeze plugs seem to happen more in the 2004. 5's and up. Iput the Opie in as more of a preventative/protection to this problem. I tow a lot, tow heavy, tow at altitudes, constant steep grades, and also a lot of desolate space here in NM, didn't want to even consider being alongside the road with the problem with a horse trailer, 4-up in 100+ temps.



CD

 

[RWood]

Another company that offers a bypass kit is WICKED DIESELS, WICKED DIESEL

 

[flyby night]

It looks like yo tap the coolant from the pipe plug in the coolant jacket at the rear of the head just above the exhaust manifold. Then run it through a relief valve, and back into the upper hose of the radiator.

My question is... . If you installed a coolant filter in place of the relief valve, wouldn't this accomplish the same thing? All you are looking for is to get some coolant to flow out of the rear of the head. In order to allow potentially less heated coolant to flow by the 5-6 part of this jacket and absorb the so potential heat spikes of the 5-6 area of the water jacket. A coolant filter will just have metered flow all the time. It will not wait until the coolant pressure rises enough to overcome the setting of the relief valve. It will also benefit your engine by providing filtration to your cooling system. Am I way off here or what?

 

[Rollin' Heavy]

Very interested in this. I do not want to see my engine with this problem. Right now I am stock but still spend a little now, saves a lot in the future!

 

[RWood]

I emailed Opie and he does not sell them anymore.

 

[CDonaldson]

Opie has distributors of his products. I got my Opie Bypass from Tim at TRE DIESEL PERFORMANCE he is a distributor of the Opie Bypass. It was a pleasure dealing with Tim, he is a great guy, quick reply, quick service.



CD