any 6.9 blocks

[pauls painting]

well as some of you remember i got a low comp. 6.9 from machine shop for my 76 f250 then buddies garage where i was storing it burnt down , what are the chances that the block is still good ? the fire got pretty hot to say the least it melted a87ford that was in there. could i re-use the pistons in another block they look ok .i have it apart . if not does some one have a good 6.9 for sale? i checked on rebuilt and dont want to spend that much on the motor yet.

 

[patternman]

I'm not sure but why would heat hurt the block? It was molten iron when it was cast. I guess if it got hot enough to get soft the bores and other cavities could
have changed their shape.

 

[82fordtruck]

Yes, heat will change the metallurgy considerab ly. Also, cast iron is a pain in the ass when it comes to heating. It is very brittle and fragile.

I can get you a block, but I think it cavitated, and it was a 7.3. I'll offer him scrap metal prices for you, and will be in STL in a few weeks.

 

[towcat]

Yes, heat will change the metallurgy considerab ly. Also, cast iron is a pain in the ass when it comes to heating. It is very brittle and fragile.

I can get you a block, but I think it cavitated, and it was a 7.3. I'll offer him scrap metal prices for you, and will be in STL in a few weeks.

I differ with you on burn jobs. Often, burn jobs are how I get good cores. Thanks to the amount of headlight switches catching on fire, most of the heat on a truck burn occurs in the cab. How do I gauge how hot the engine compartment got? By inspecting the plastic and rubber parts on the motor. the heat is most concerntrated in the upper and outer parts of an engine compartment on most burns. Judging by the amount and the inensity of the melt determines hot hot did the engine get. Obviously, the more melt the larger the motor will be suspect. Plusses are motors found with injector line caps intact and the valve cover gaskets intact. Lastly, the new EPA reglations favor the "heat/furnace" meathod to clean blocks and heads. how hot do you think the furnace needs to get for the same oil/grease to char? Hint...its the same temps as a engine fire.

 

[94f450sd]

i agree with towcat.ive gotten many good engines from burnt cars/trucks.i had one that was so hot it melted the carb and distributer.i knew the motor was good so a regasket and valve seals,stuffed it in a car and its still running today.that was 8 years ago.

 

[pauls painting]

so i can re gasket the motor and run it? what about the injectors and glow plugs? can i reuse these i know i have to replace the ip or can i have it rebuilt also? need one of kens stage 1 pumps .

 

[82fordtruck]

I differ with you on burn jobs. Often, burn jobs are how I get good cores. Thanks to the amount of headlight switches catching on fire, most of the heat on a truck burn occurs in the cab. How do I gauge how hot the engine compartment got? By inspecting the plastic and rubber parts on the motor. the heat is most concerntrated in the upper and outer parts of an engine compartment on most burns. Judging by the amount and the inensity of the melt determines hot hot did the engine get. Obviously, the more melt the larger the motor will be suspect. Plusses are motors found with injector line caps intact and the valve cover gaskets intact. Lastly, the new EPA reglations favor the "heat/furnace" meathod to clean blocks and heads. how hot do you think the furnace needs to get for the same oil/grease to char? Hint...its the same temps as a engine fire.

I know very little about burned vehicles. We deal at work with industrial cast iron parts. Large changes in heat such as spraying it with a fire hose can permanently ruin any casting. They are very brittle, and impacts or localized heating can cause cracking. Also, getting it real hot can change the metallurgy. It is possible that vehicle fires don't get too hot, which wouldn't damage much of anything. I really don't know.

However, I would look at the indicators towcat mentioned and see wht is burned before buying, because I know that there CAN be very extensive damage, even if it's not normally there.


Here's my suggestion - get it magnafluxed first. That way, none of this is guesswork.

 

[82fordtruck]

as far as baking the casting - you are correct. It gets hot. I think they baked some castings we had in last week at around 5-600 degrees F. The big changes come at 737 degrees C. If it's been above that - run like hell. I don't care what anybody says.

 

[94f450sd]

lets see here my EGTs get up to 1200 degrees on the highway.my heads are cast iron as well as my exhuast manifolds.guess i gotts get rid of it then.my PSD hits 1500 degrees on the track and 1400 on the street.guess i should get rid of that also?

 

[Mr_Roboto]

I used to work at Ford's casting plant in Cleveland, we poured the blocks at 2700* F.

I say use the block. Replace anything with rubber in it that could have been damaged by the heat.

As was suggested above, I would check for cracking or warpage in case the engine was hosed directly with water.

 

[typ4]

Get it magnafluxed and if ok have them hone the bores a little and of course check them for roundness. If the mainline is straight then it "should" be ok. Just inspect everything measure twice cut once , wait that is wood. :Sly
I used to work for an excavating co. that had several pieces of equipment in a building that burnt and it got hot enough to melt the radiators some and sag a couple of the rollbars. we did minimal gasketing to check run the engines a few injectors and lines and pumps and to our amazement all ran for many years. They were all JD engines and I saw the firemen put very cold water on way hot metal, wasnt a good day. But anyway that is my experience base. I say go for it if it is straight and crack free.
Russ

 

[sle2115]

Lastly, the new EPA reglations favor the "heat/furnace" meathod to clean blocks and heads. how hot do you think the furnace needs to get for the same oil/grease to char? Hint...its the same temps as a engine fire.

500 degrees for cast iron, did it for several years as a machinist! I don't think this was an engine fire though, from what I gather, it was in a building that burnt up, could have been much more heat or much less. I think checking the plastic parts would be a good clue though!

 

[82fordtruck]

lets see here my EGTs get up to 1200 degrees on the highway.my heads are cast iron as well as my exhuast manifolds.guess i gotts get rid of it then.my PSD hits 1500 degrees on the track and 1400 on the street.guess i should get rid of that also?

I said degrees C. Plus, the head doesn't get that hot, just the exhaust. Iron begins to melt and undergo changes that weaken it at that temp.

 

[Mr_Roboto]

I'll translate. 737*C = 1358*F, i.e really freaking hot.

 

[94f450sd]

I said degrees C. Plus, the head doesn't get that hot, just the exhaust. Iron begins to melt and undergo changes that weaken it at that temp.

ok tell your exhuast ports and valves that they dont get that hot.