coolent passages on head gaskets?

[Part time]

Why are the coolant passages so tiny on the head gaskets compared to the heads?

 

[G. Mann]

Diesel engine is a compression ignition engine. By keeping the head "hot" it enhances combustion thus ignition.

It also likely is why the heads are so often cracked .. the cast iron head does a delicate balance between retaining enough heat to augment combustion to "light off the vaporized fuel" and not having to much heat to damage the head.. Heat up and cool down times have to play a big part in that dance as well.. I think.

Google "Hot Bulb Diesel Engines" and watch how some of the early diesels were started, and kept running... might help understand why coolant passages are what they are... maybe..

 

[Part time]

Thanks I'll search that. I was thinking about making the hole bigger on a new set of gaskets. I wonder how much cooler these engines would run??? I bet the guys are trying to get some really good horsepower out of them probably working there benefit?

 

[OLDBULL8]

All the 6.9 7.3 IDI gaskets are like that. Pic just show one that's blown.

 

[Part time]

Thanks I'll search that. I was thinking about making the hole bigger on a new set of gaskets. I wonder how much cooler these engines would run??? I bet the guys are trying to get some really good horsepower out of them probably working there benefit?

 

[chris142]

The holes also help direct coolant. If you go modifying them another part of the engine may not get the correct coolant flow. Don't go trying to re engineer the wheel

 

[OLDBULL8]

Thanks I'll search that. I was thinking about making the hole bigger on a new set of gaskets. I wonder how much cooler these engines would run??? I bet the guys are trying to get some really good horsepower out of them probably working there benefit?

No, your not going to get a whole lot of HP out of them without a lot of $$$$$$$$$$.

Run these engines at 190 - 205 F degrees. It's a frigging Diesel.

 

[Part time]

I love this site. My name is seth and i live in nh . The salty state i call it. Thanks for all the in put. That engine come out of a junker i bought at at a famliy owned junk yard . it's 6.9 that im going to fresh up. It ran fine,the only thing i could find. A couple of the crank bearings had scuff marking on then. No head gasket modifications for me, well may if i had lotes of money and time to kill. Lol

 

[icanfixall]

If this was a 7.3 engine you can modify the head gasket by installing a 6.9 head gasket on the 7.3. The only difference in the 6.9 to 7.3 gasket is the 6.9 has an open coolant port on the lower edges where the 7.3 does not. Both gaskets measure exactly the same. I have done plenty of measuring and know this "new idea" works well. Many years ago Mel and I were talking about why the 7.3 engines traditionally ran hotter than the 6.9. We both felt it was the head gasket change. We have several members that have installed the 6.9 gaskets on the 7.3 and are very happy with the results. Had I known then what I know now I sure would have installed 6.9 gaskets on my 7.3. Every 7.3 has round ports plugged off in the heads and the block. So instead of removing those plugs just measure the coolant passage in the 6.9 gaskets and make that size hole in the plugs.

 

[DaveBen]

Diesel engines are HEAT ENGINES and running them cooler than normal is not good for the engine or economy. Leave it alone.

Dave