6-71 diesel

[jdw]

Looking into a 6-71 anyone have info on the fuel usage? Running a saw and edger?

[Satamax]

Not yet sorry.

Tho, i hope you know they are noisy! Real noisy!

[ozarkgem]

I have never ran one but I would guess 4-6 gal per hr. We will see how close I am from someone who actually uses one.

[jdw]

I know there loud but there a powerhouse. Plus I kinda like the way they sound lol ;D

[Satamax]

I know there loud but there a powerhouse. Plus I kinda like the way they sound lol ;D

I have piled strawbales around mine. On three faces. About 3 ft away.  Cuts the noise a bit. I might be the only nutter in France, running a detroit genset!  ;D

Ran it a while yesterday. To power the saw. I'm having troubles! The RPM drop when i hit the delta ( triangle) position at startup!

Here's when i got it! :D

https://www.youtube.com/watch?v=0EmkLpbYiA0

[jdw]

Yep that's the sound of a Detroit  ;D

[barbender]

@Gearbox runs a circular mill powered with a DD at the local threshing show, I didn'the even realize it was a DD until I looked closely at the engine. They have the stack terminate about 12' up in the air, and it is amazingly quiet.

[SineWave]

I know there loud but there a powerhouse. Plus I kinda like the way they sound lol ;D

Lol, me too! I've got a Deutz air-cooled diesel on my engine driven welder and that sounds pretty sweet, too!

https://www.youtube.com/watch?v=A0PY1te8DIM

[Bert]

I use a 671 on my Frick. It uses about 2 gal an hr governed at 2100RPM.

[Satamax]

I use a 671 on my Frick. It uses about 2 gal an hr governed at 2100RPM.

Not bad!

I can expect less on mine at 1500rpm then!

[ozarkgem]

I use a 671 on my Frick. It uses about 2 gal an hr governed at 2100RPM.

better than I thought. Not bad considering how much you can saw in an hour

[Bert]

No not bad at all. Fuel use has never been a complaint of mine. We do about 4500 FT in 6-7 hrs. Which includes shutting the mill off to cut up lumber to length and load logs on the deck. Alot of blocking but some grade and pallet boards.  Detroits are pretty common around here as power units. At least they were until everybody closed up shop due to markets :-\

[Satamax]

Well JDW, sorry i'm hacking a bit your thread.

Is there anybody here, who know the causes of the emergency stop flap closing?

Yesterday, it stopped on me again. The temp was at 100C° normally it's more like 80C°/90C°

The blower casing was verry hot.

Or may be some of you know a troubleshooting chart somewhere on the net?

I have read and reread the manuals i have. And there is little on the emergency flap.

Thanks a lot guys.

Max.

[ozarkgem]

Well JDW, sorry i'm hacking a bit your thread.

Is there anybody here, who know the causes of the emergency stop flap closing?

Yesterday, it stopped on me again. The temp was at 100C° normally it's more like 80C°/90C°

The blower casing was verry hot.

Or may be some of you know a troubleshooting chart somewhere on the net?

I have read and reread the manuals i have. And there is little on the emergency flap.

Thanks a lot guys.

Max.
I will look at mine but I wonder if the catch is worn and it is just not holding due to the vibration of the motor. I am really not sure how they are set up to trip during a runaway. How many hrs on your unit? Maybe you could find a used intake unit and replace the whole thing.

[SPD748]

Is there anybody here, who know the causes of the emergency stop flap closing?

Post a picture of the blower housing. Some are actuated by an air cylinder or electric solenoid. Most stationary engine flaps are manually activated either by remote cable or a small knob on the flap shaft itself. If it's arranged this way, there is a notch in the flap shaft that holds the flap open. That can become worn causing the flap to jump off the notch due to the vibration of the engine.

-lee

[Satamax]

Hi guys!

Thanks a lot for your replies.

Ozarkgem, no idea on the hours.  It's a GM stamped detroit. Baring just a 6-71 N on the plate. It's been redone in the sixties or seventies with a french alternator. As the wiring clearly shows, it's not a fourties or fifties one.



But has some copper acid etched plates on the doors for maintenance and greasing plans, which bear a contract number from 29 june 1944. Hence my guess on the rebuild.

SPD748, it's actuated by a solenoid, visible on the left of the blower here.



Thanks a lot for your help guys. One detail. I'm running the radiator open, as i don't have a radiator cap. So the thermostat might not oppen?

[Satamax]

Well JDW, sorry i'm hacking a bit your thread.

Is there anybody here, who know the causes of the emergency stop flap closing?

Yesterday, it stopped on me again. The temp was at 100C° normally it's more like 80C°/90C°

The blower casing was verry hot.

Or may be some of you know a troubleshooting chart somewhere on the net?

I have read and reread the manuals i have. And there is little on the emergency flap.

Thanks a lot guys.

Max.

Hi Guys.

Sorry for the digging.

Well, it's acting the same again.

I have downloaded some manuals.

One question thought, would you run it without the thermostat? (calorstat i don't know or can't remember the name of this part in english)  If this one is flakey. This would may be help. I want to keep hobby sawing. I saw a trunk every now and then. I sawed a cubic meter of wood yesterday. Might saw one or two more in the next fortnight.

Has anybody ever cleaned the  cooling circuit.  Sandplugs and all?

I would like to know how it's done.

Thanks a lot guys.

[Satamax]

So, checked if there was a thermostat, ans there's none un thé thermostat housing.

Tho, it's seemingly overheating. I realy dont know wha to do.

Obvious one, check the water pump. How?

Last year,  emptied the whole engine, coolant wasn't that bad. Rusty collor, but no mud.

Anybody knows where are the sand plugs?

[Bert]

Couple questions. What is the actual issue as im having a hard time following? Is it the blower flap? Air actuated or mechanical this is just a safety thats user thrown. If its closing when its not supposed to its no sign of engine trouble. For overheating, do you run a temp gauge? If no rad cap and no thermostat Id have to believe it would be throwing steam out even slightly above ambient temp.

[Satamax]

Hi Bert!

Thanks for your reply.

It's solenoid actuated. Well, seemingly it overheats slightly. 100c° instead of the recomended 90c°.  And then the dang flap closes.  No thermostat. Radiator seemed to be clean. Last time i drained it. No sign of mud. I'm a bit stumped.

[Satamax]

I have a radiator cap. 7lbs one.

[Bert]

I dont think the issues are related at all. That flap is just a safety to stop a run away engine. I cant believe it would be tied to an overheating problem. Id take the solenoid off and just make it a mechanical flap. Something you could trip if the situation called for it. Its not a good thing for it to be closing. It will suck the seals out of your blower.

[Satamax]

Bert, this solenoid actuated flap is linked to the temperature sensors. I think the best i can do, is buy a new  water pump. Drain the coolant, run water with a cleaning agent for some time. Then hose the innards. And get back to -35c° coolant.

[bandmiller2]

Max, that genset was left over from the great war. I would suspect restrictions in the cooling system. Checking the water pump is good form they are rebuild able but one that old should probably be replaced. The emergency shut down should be operable but not used, as Bert says its hard on the seals to trip. You could retain the solenoid but not have it tied to the temperature sensor. Unless that engine was modernized its an old two valve head with "J" injectors. You will always get smoke from it. Later detroits went to a four valve head and "N" series injectors, to cure its smoking habit. To clean the cooling system I use oxalic acid, run for a wile then drained flushed and neutralized with baking soda. Frank C.

[Satamax]

Thanks a lot Franck.

Yep, ww2 genset. Modernized in late 60 early 70's.
Alternator is a french one. Of proper specs.  I wonder how i could test the pump. As well, i'm not asking much. 22kw. For a 80kw alternator.

If it gets all messy, i'll resell the 6-71. And use the unic V8 i gonna buy on a broken snowblower later tonight. Might even resell the genset, and ask a friend to resell me another alternator he has in stock.

[Bert]

Ahhh ok. Ive never seen one set up like that. Pretty fancy to have an overtemp condition close the flap. Agree its prob best to just clean/flush it all out and see what happens with the temp. I had one that the block cracked and was doing all kinds of weird things. The ones made during the war were produced so fast the blocks didnt cure properly and were prone to cracks I was told.

[bandmiller2]

Max, what is the standard cycles (hertz) used in your country.?? Depending what your genset was used for it may not match your new mills motor. Ours is pretty much standard 60 cycles. Frank C.

[Satamax]

Thanks a lot Frank, for your reply.

Well, i'm running 1500 rpm, 50HZ 380V (well, a smidge low at 375vac)

The alternator is a french one. Don't know when it's been retrofitted to this. But all the wiring is late sixties or seventies. Everything should be fine.

If the worse comes, or if i get really fed up with this. I have just scored a "unic" V8 of 852 ci. With only 105 hours. in my snowblower.

https://forestryforum.com/board/index.php/topic,97397.0.html

I think this detroit gonna go to WW2 heavens. I mean, to a collector.  And i will run a monster slower, as i have a 2 speed transmission behind the V8. I'd like to run it at idle, or a bit more. And still produce power. Only problem, i have no governor on the engine. But nothing which can't be fixed with electronics.

[Satamax]

Same engine as this one.

https://www.youtube.com/watch?v=3u73mfAtq7w

[Satamax]

Dang thing.

Overheated again today. Above boiling point.  Steam Comming out   >:(

[gmmills]

Satamax

     Try pulling the water pump and check the end of the drive shaft mounted in the blower housing. Make sure it is not warn or broken. Just need to confirm that the pump drive is actually rotating the water pump. I have seen this only one time many years ago. Virtually did everything you have previously tried to no avail. It ended up being the water pump drive shaft had warn past proper engagement, just slipped. No pump rotation.

[Satamax]

Ok, thanks a lot for your reply.

I know i have to do it. But, i need containers to save the coolant. It's new from last year (ok, not new then) and the engine has been run only 5 or six times since.

I need to address this.

Thanks again.

Max.

[sealark37]

A diesel that overheats with no obvious problem usually has a blown cylinder head gasket.  How many hours on your engine since overhaul?    Regards, Clark

[Satamax]

Hi Clark.

I should admit, i have no idea. I have started draining it. But ran out of containers. There's no mayo in the coolant.

[Satamax]

Well, taken the pump appart, locks on the drive. Pump seems real nice. But trying to bleed the oil heat exchanger,  nothing comes out.  Next step, open and check.  Head gasket is real oily.

[Satamax]

Taken the ruber pipe at the bottom.  Water flows through.  Depressing!

[Grizzly]

Nobodies mentioned it so maybe I'm way out in left field. I notice that screamer being run at 1500rpm. Any Detroit I've run and any mechanic I've been taught by says that those old detroits should not be laboured or loaded below 1900rpm. On our old truck (1980 Ford L8000 w/6-71N) it is very noticeable that as soon as you work the engine below 1800rpm temperature rises quickly. From what I remember exhaust temps rise very high (over 1200F) when you get into those lower rpms. I know there's some experts on here and I'm not trying to be one just offering my tidbit.

[Satamax]

Thanks a lot Grizzly.

That's mad. An engine you can't run at low rpm? Or it overheats? Well, i have to tap for the broken stud on the pump. Reassemble everything, refill with coolant. And run it when it's colder. I don't have high hopes. All the circuit is clean. I really wonder what is going on. I looked at the coolant, flashy yellow originally. Now it's brownish. Is it the rust, or is it exhaust gases getting in the coolant, because of a blown head gasket. I washed the whole circuit today.

If it continues to overheat, in goes the V8.

[Kbeitz]

At a race shop you can buy a water wetter. It makes your water wetter and help
the rad keep things cool. It really works.

[Satamax]

I was looking that way too.

Thanks Kbeitz

[dgdrls]

Nobodies mentioned it so maybe I'm way out in left field. I notice that screamer being run at 1500rpm. Any Detroit I've run and any mechanic I've been taught by says that those old detroits should not be laboured or loaded below 1900rpm. On our old truck (1980 Ford L8000 w/6-71N) it is very noticeable that as soon as you work the engine below 1800rpm temperature rises quickly. From what I remember exhaust temps rise very high (over 1200F) when you get into those lower rpms. I know there's some experts on here and I'm not trying to be one just offering my tidbit.

I agree, 1500 loaded seems too slow for a 2 cycle Detroit.
I would reach-out to DD or MTU for advise on optimum operating RPM range.

D

[Satamax]

Well. It's a gen set. So no choice!

I'm finding informations on the motor change.

It's not simple, single bearing alternator.  Seems to be sae#2 or something close on the GM. Sae#1 on the unic. Adapter is a welded thing. Dont know if there's a centering lip. I have enough meat to redrill for sae#1. The latest question is the coupling. The udea is growing on me. Only prob. Lack of time!

[Satamax]

I'm a dimwit!

Last time i tried to saw, i didn't pay attention, hertz were good. But yesyerday, i checked with the dmm. And my voltage was way off! 257vac, when it should be normally around 380. So i raised the presets a notch. Checked again,  376vac, and 53hz. (50 normally here) So i was all good. Sawed all afternoon. Didn't rise above 95 celsius. So, grizzly was partially right. I think, running a 29kw motor, meant for 380,  on 257 volts was loading the engine too.

Thanks guys!

[Grizzly]

I'm a dimwit!

Don'tcha hate days like that!!  :D

[Satamax]

I'm a dimwit!

Don'tcha hate days like that!!  :D

Yep, definitely!