Cummins 4BT & Diesel Conversions Forums banner
1 - 20 of 49 Posts

·
Registered
Joined
·
1,002 Posts
Discussion Starter · #1 ·
I ran into a diesel machanic the other day and was questioning him about cooling. The first question he asked was “are you running a bypass”? I didn’t know what that was, so I did some research. I found two threads on here. One of them I even commented on. Of course, this was years ago and I knew less about it than I do now. Lol.

This is what I’m talking about.


Anyways, the kit claims to lower the temperature and pressure at the last two cylinders. All of these kits and all of the discussion on here seem to be about 6 cylinders. Has anybody done this on a 4BT? Would there be a benefit?
 

·
Registered
Joined
·
13,325 Posts
Well, the 4bt has the same issue with the rear cylinder. #4 is far hotter than the front three. It's just the nature of how the cooling flows. It is interesting that the kit has parts that are much like factory Cummins items. That rear freeze plug was used for engines running an air compressor so a part similar to that custom one can be had from factory parts. See photo below. You'd have to figure out how to plumb the return up at the thermostat. Those kits are for the common rail engines, not the standard B series. I'm sure it could be done.
 

Attachments

·
Registered
Joined
·
334 Posts
I ran into a diesel machanic the other day and was questioning him about cooling. The first question he asked was “are you running a bypass”? I didn’t know what that was, so I did some research. I found two threads on here. One of them I even commented on. Of course, this was years ago and I knew less about it than I do now. Lol.

This is what I’m talking about.


Anyways, the kit claims to lower the temperature and pressure at the last two cylinders. All of these kits and all of the discussion on here seem to be about 6 cylinders. Has anybody done this on a 4BT? Would there be a benefit?
I suspect, the 6 cylinder temp issue, is more from intake air not flowing evenly into cylinders. GATES has addressed this with his twin intake manifold for certain year 6bt Cummins.
 

·
Registered
Joined
·
1,002 Posts
Discussion Starter · #5 ·
Today I ran the truck on the highway. I quickly pulled over and checked the exhaust manifold with a temp gun. I checked at each cylinder. The hottest cylinder was the rear and they progressively got cooler going forward. You might say it’s a smoking gun, but I have to say, it only got cooler by about 10-15 degrees for each one.
 

·
Registered
Joined
·
316 Posts
Well, the 4bt has the same issue with the rear cylinder. #4 is far hotter than the front three. It's just the nature of how the cooling flows. It is interesting that the kit has parts that are much like factory Cummins items. That rear freeze plug was used for engines running an air compressor so a part similar to that custom one can be had from factory parts. See photo below. You'd have to figure out how to plumb the return up at the thermostat. Those kits are for the common rail engines, not the standard B series. I'm sure it could be done
Well, the 4bt has the same issue with the rear cylinder. #4 is far hotter than the front three. It's just the nature of how the cooling flows. It is interesting that the kit has parts that are much like factory Cummins items. That rear freeze plug was used for engines running an air compressor so a part similar to that custom one can be had from factory parts. See photo below. You'd have to figure out how to plumb the return up at the thermostat. Those kits are for the common rail engines, not the standard B series. I'm sure it could be done.
Thanks . Char. I don’t know about the 6b but the 4b in my tractor , is the same as the #5 picture down of the one the fellow has putting it into a 95 Bronco, you see a pipe plug in the back side of the head at #4 cyl , that is where I originally had a 1/2”street 90* feeding water to the cab heater , with the return in the bottom of the lower radiator hoe bracket. I also for some reason have 2 heat sensors just before the thermostat.
So can I remove one of those sensors & connect a 5/8” heater hose back to that port in the head, which would increase the water flow of #4 cyl ?
 

·
Registered
Joined
·
316 Posts
Today I ran the truck on the highway. I quickly pulled over and checked the exhaust manifold with a temp gun. I checked at each cylinder. The hottest cylinder was the rear and they progressively got cooler going forward. You might say it’s a smoking gun, but I have to say, it only got cooler by about 10-15 degrees for each one.
That is quite the temp difference ,, 10-15 degrees for each cyl . For a 6 cyl that equals 60- 90* temp differential from front to back.
I don’t think that is what you meant , probably 10-15* for whole engine? Yes?
 

·
Registered
Joined
·
1,002 Posts
Discussion Starter · #8 ·
That is quite the temp difference ,, 10-15 degrees for each cyl . For a 6 cyl that equals 60- 90* temp differential from front to back.
I don’t think that is what you meant , probably 10-15* for whole engine? Yes?
Been awhile now, but I think it was each cylinder. Maybe 50 degrees for the whole engine.
 

·
Registered
Joined
·
316 Posts
Ok bu
Been awhile now, but I think it was each cylinder. Maybe 50 degrees for the whole engine.
Ok, but that sure sounds like a lot, I would think that would work the head. Char 1355 post above suggests a kind of bypass out of cyl #4 or #6 & back into the head just before the thermostat. There is a pipe plug on the head right behind the fuel filter, (at least there is on a 4bt, which is what I have, & you will see above in this thread, where I posted a response to Char & asked the question if a bypass could go to the front, where I have 2 heat sensors, because I am also having heat issues. If anyone can give me a response to that, I would greatly appreciate your help. Thanks.
 

·
Registered
Joined
·
334 Posts
Ok bu

Ok, but that sure sounds like a lot, I would think that would work the head. Char 1355 post above suggests a kind of bypass out of cyl #4 or #6 & back into the head just before the thermostat. There is a pipe plug on the head right behind the fuel filter, (at least there is on a 4bt, which is what I have, & you will see above in this thread, where I posted a response to Char & asked the question if a bypass could go to the front, where I have 2 heat sensors, because I am also having heat issues. If anyone can give me a response to that, I would greatly appreciate your help. Thanks.
Consider, the 4BT has been used with quite a few different cooling system configurations. However, having heater cores open when filling a cooling system is a must. The there is cavitation, which is the single greatest issue, in any cooling system, this is why the after market has developed water-less coolants like EVANS.
 

·
Registered
Joined
·
2,601 Posts
I ran one of my own construction until I went with the diesel ZF, the adapter conflicted with it's location so it is no longer in place.
I routed it from the rear freeze plug in the block to the port in front of head down stream from the thermostat with a ball valve in the circuit this was used as a restrictor to control flow. The biggest plus I saw was in winter the coolant would settle down much faster from a cold start without it 20-35 minutes to totally stabilize without it 45-60.
From what I have observed without one there is a 15-20 degree diff in coolant temp from front to back on the 4bt with one about half the difference...$.02
 
  • Like
Reactions: Papa and SUBRUTUS

·
Registered
Joined
·
316 Posts
Consider, the 4BT has been used with quite a few different cooling system configurations. However, having heater cores open when filling a cooling system is a must. The there is cavitation, which is the single greatest issue, in any cooling system, this is why the after market has developed water-less coolants like EVANS.
A waterless coolant ? Really ? EVANS ? Don’t know about any of this.
 

·
Registered
Joined
·
316 Posts
I ran one of my own construction until I went with the diesel ZF, the adapter conflicted with it's location so it is no longer in place.
I routed it from the rear freeze plug in the block to the port in front of head down stream from the thermostat with a ball valve in the circuit this was used as a restrictor to control flow. The biggest plus I saw was in winter the coolant would settle down much faster from a cold start without it 20-35 minutes to totally stabilize without it 45-60.
From what I have observed without one there is a 15-20 degree diff in coolant temp from front to back on the 4bt with one about half the difference...$.02
Thanks. Never connected the dots that eggman 918=Subrutus
So when you did your own setup it helped, good ! & you said you put in a ball valve to regulate flow, how big was the bypass hose & how much did you restrict it ? Where did you put the water back into the system ?
I took some pictures to show the 2 heat sensors at the front of the head & where my delegated heater hose was connected at the rear behind the fuel filters & now has an auxiliary heat sensor for a diff gauge . The 2 sensors, I connected with a yellow wire, to show. & The last pic is the aux removed & its measurement diameter & about 1” long that would go into the bottom of a 1/2” tee . Out the top of tee , though the lifting ring , over the top of the Rockers , to a 1/2”-90* on top of a 4”long into the heat sensor tight to the #1 rocker cover .
Connected by 5/8” hose, or would you say to better use something diff ?
Motor vehicle Wood Gas Machine Nut
Electrical wiring Gas Electrical supply Cylinder Metal
Automotive tire Finger Gas Auto part Cameras & optics

What do you think??
 

·
Registered
Joined
·
316 Posts
I ran one of my own construction until I went with the diesel ZF, the adapter conflicted with it's location so it is no longer in place.
I routed it from the rear freeze plug in the block to the port in front of head down stream from the thermostat with a ball valve in the circuit this was used as a restrictor to control flow. The biggest plus I saw was in winter the coolant would settle down much faster from a cold start without it 20-35 minutes to totally stabilize without it 45-60.
From what I have observed without one there is a 15-20 degree diff in coolant temp from front to back on the 4bt with one about half the difference...$.02
Ok I got it now Subrutus gave eggman a thumbs up ! Sorry !
 

·
Registered
Joined
·
2,601 Posts
I made a "plug" that fit the bore with a O ring to seal it was retained with a internal cross bar that accepted a bolt much like the way a block heater is installed, this had a 3/8 NPT thread for the plumbing.
 
  • Like
Reactions: SUBRUTUS

·
Registered
Joined
·
316 Posts
Consider, the 4BT has been used with quite a few different cooling system configurations. However, having heater cores open when filling a cooling system is a must. The there is cavitation, which is the single greatest issue, in any cooling system, this is why the after market has developed water-less coolants like EVANS.
I made a "plug" that fit the bore with a O ring to seal it was retained with a internal cross bar that accepted a bolt much like the way a block heater is installed, this had a 3/8 NPT thread for the plumbing.
Thanks eggman ! Did the head not have a plug in it where mine does ? So your line was a 3/8”, & you still had to reduce the flow, that was one of my concerns , as that there is the possibility of stealing to much water & passing it all the way up to the thermostat, depriving that side of the head . So you used a 3/8” line & ball valve. How much did you turn the valve %?
The exit in the back of the head is 1/2” pipe & the auxiliary heat sensor has to screw into a 1/2” pipe thread. As you see I have a 2” nipple started in that hole & I would require a 1/2”tee on the end of it, to install the sensor, out the top of the tee with a 3/8” hose barb .
At the return end , by #1 rocker cover, a reducing bushing , a short piece of 3/8” pipe , 90* elbow & again a 3/8” hose barb
What do you think ? I value what you call your 2 cents worth !
Again thanks for your patience & responses
 

·
Registered
Joined
·
2,601 Posts
Thanks eggman ! Did the head not have a plug in it where mine does ? So your line was a 3/8”, & you still had to reduce the flow, that was one of my concerns , as that there is the possibility of stealing to much water & passing it all the way up to the thermostat, depriving that side of the head . So you used a 3/8” line & ball valve. How much did you turn the valve %?
The exit in the back of the head is 1/2” pipe & the auxiliary heat sensor has to screw into a 1/2” pipe thread. As you see I have a 2” nipple started in that hole & I would require a 1/2”tee on the end of it, to install the sensor, out the top of the tee with a 3/8” hose barb .
At the return end , by #1 rocker cover, a reducing bushing , a short piece of 3/8” pipe , 90* elbow & again a 3/8” hose barb
What do you think ? I value what you call your 2 cents worth !
Again thanks for your patience & responses
That is what I did pretty much, the ball valve was open 20%-30% I think that is close enough for you to run it I tinkered with it for a week or so to where the gauge that is in the rear port on head would stop swigging and settle down. It does not take a lot of flow from the rear of the water jacket to even things out it really seems to change the whole flow dynamic.
 

·
Registered
Joined
·
1,002 Posts
Discussion Starter · #19 ·
A waterless coolant ? Really ? EVANS ? Don’t know about any of this.
Ive done a lot of research into the waterless coolant. It has a number of good features, but there are some bad ones too. The biggest is that it doesn’t cool quite as effectively.
 

·
Registered
Joined
·
316 Posts
That is what I did pretty much, the ball valve was open 20%-30% I think that is close enough for you to run it I tinkered with it for a week or so to where the gauge that is in the rear port on head would stop swigging and settle down. It does not take a lot of flow from the rear of the water jacket to even things out it really seems to change the whole flow dynamic.
Thanks. So a 3/8” line, with ball valve open 30% would reduce line to about 1/8 . Yes that is not much.
Where did you return it too? -?
I don’t know the pattern of the water flow galleys, but it seems to me that taking water out of the block under the head would be depriving the head of water especially #4 cyl .
As I said early on, that part of the head that I show with the temp sensor, had a 1/2” street 90* a reducing bushing & a short piece of 3/8 pipe with a 5/8” heater hose to the tractors cab heater & returned below the water pump to the lower radiator hose connection, with a shut off valve there, with 3/8” pipe connection, so when open it really circulated the water, but since I don’t need a heater , I had it shut off, but oil rotted the hose & it blew, lost all the water & blew the engine, that is why I eliminated it & I installed an extra gauge with a buzzer & numbers, instead of colors & (that over your right shoulder when driving) , mounted it & an actual oil pressure gauge at the steering wheel.
So I don’t think a hose connected from that port in the head to just before the thermostat would circulate as much coolant as when it went through the heater . BUT I may be wrong !
Thanks again !
 
1 - 20 of 49 Posts
Top