8v71 Detroit

[KyIH 4]

I have a 8v71 Detroit in a grain truck that has started having some overheating issues and has started dripping coolant from the breather tubes. Any thoughts on this would be appreciated.  I have never opened up a Detroit, I have heard they can be tricky to work on. Any truth to this?

[AKwelder 1,949]

I think they are pretty simple, just a little different 

 

coolant from the breather tube does not sounds good, best of luck

[Rawleigh99 826]

Find an older Detroit mechanic.  The young guys don't have the experience with these engines or the tool set to work on them.  They are pretty simple really, but are so different as AK said, that  of what you may know about diesels doesn't apply.

Here is some basic material on the inline 4 and 6-71, but some of it applies to their V brethren.

http://www.tractorparts.com/PDFs/DETROIT_DIESEL_IN-LINE_71_SERIES_1950_TRUCK_AND_COACH_SVC.pdf

Parts source:

https://dieselpro.com/

[b&c farms 18]

if i remember right that have quad rings around the water jackets if all you are going to do is replace the upper end on it not to bad sleeve height should be ok the only hard part is setting the rack and injector height it just takes time and patience when you get ready to start it after you are all done have a piece of plywood that is bigger than the blower intake in case it starts to run away put the board over it to kill it 

[KyIH 4]

Thanks guys. I am weighing my options on what to do with it. It had a fair amount of water in the oil along with some metal shavings. I definitely don’t want to spend big $$$ for a rebuild. 

[Injpumped 245]

71 series is a dry sleeve engine.

[KyIH 4]

Would that be more or less costly for a rebuild?

[b&c farms 18]

they are not that bad to rebuild just a few things to watch for wrist pin keepers check with a vacuum sleeve height and when you run the rack have someone that has rebuilt the blower work on it that has down them before 

[KyIH 4]

Any idea on how much a rebuild would cost?

[jeeper61 1,165]

Search around a bit I have seen some government surplus 8v92s for cheep so you might find a 8v71 

[Lazy WP 596]

5 minutes ago, jeeper61 said:

Search around a bit I have seen some government surplus 8v92s for cheep so you might find a 8v71 

Pull out the 71 and slap the 92 in. Way better motor imho

[jeeper61 1,165]

I liked those last 8v92 Silvers from the early 90s.

My buddy had one in a L9000 with a 13 speed 435HP ran down the road pretty good.

[KyIH 4]

What else would fit without major modifications? Cummins, cat, IH? It’s a gmc 9500 with 13 speed. How about a dt466?

[806 man 762]

9 hours ago, KyIH said:

Thanks guys. I am weighing my options on what to do with it. It had a fair amount of water in the oil along with some metal shavings. I definitely don’t want to spend big $$$ for a rebuild. 

With metal shavings in the pan you have serious issues. Not sure about 8-71 but some screamers didn't have a water pump pee hole and were known to lose the seal and take out crank shaft and bearings. As mentioned above silver's are good engine. 6V92TA would be a nice swap. Be aware of green engines painted and rebadged as a silver they are not the same animal.

[KyIH 4]

Yeah, The seals on the water pump did go out and dump water in the oil. It didn’t run long that way, but I’m sure it didn’t help it. I’m thinking a swap may be my best option. Would a 6v92 bolt up in place of a 8v71?

[806 man 762]

3 hours ago, KyIH said:

Yeah, The seals on the water pump did go out and dump water in the oil. It didn’t run long that way, but I’m sure it didn’t help it. I’m thinking a swap may be my best option. Would a 6v92 bolt up in place of a 8v71?

I doubt it would be a direct bolt in since one is a 8-V and other 6-V.  Not sure If a 8V92N would bolt in but that would be a nice up grade for a little more HP.