RonMar
Elite Member
With the ammount of pressure involved in a Diesel cylinder, I believe only a proper head gasket between a head and block with a true surface, properly torqued in place is going to contain it.
Another way to check for a headgasket leak is to hold your thumb over the overflow hose or attach a low pressure gauge(combination vacume/pressure gauge) with a hose barb fitting MOMENTARILLY to the hose while running to see if there is any pressure build up on that hose. You could also put the hose in a container of water to look for bubbles. If these things had an overflow resovoir, a leaking headgasket would be showing bubbles in the overflow resovoir. A leaking headgasket will add combustion gasses to the cooling system and pressurize it to the point that the radiator cap pressure is reached. The excess pressure is vented out the overflow tube. Just don't leave that overflow hose blocked. If there is a head gasket leak, the pressure will continue to build and without a way out, will eventually rupture the cooling system.
As far as cleaning the radiator goes, I made up a new blowgun attachment the other night from a old piece of aluminum arrow shaft about 3/8" in diameter(2217 shaft)and about 24" long. I capped the end and drilled a 1/8" hole in the side of the tube wall about 1/2" from the end so it blows air at a 90 degree angle from the tube. I can slide this straight tube down through a small gap in the radiator shroud located at the top rear corner of the radiator on both sides. Using this access point, I can get this straight pipe down between the rear of the radiator and the front of the fan and apply air directly to the entire rear surface of the radiator without having to disassemble anything. I have been using a shopvac to clean the radiator. I used this air tube after a vacume session the other night and got a ton more debris and sand/dust out of the air passages.
Another way to check for a headgasket leak is to hold your thumb over the overflow hose or attach a low pressure gauge(combination vacume/pressure gauge) with a hose barb fitting MOMENTARILLY to the hose while running to see if there is any pressure build up on that hose. You could also put the hose in a container of water to look for bubbles. If these things had an overflow resovoir, a leaking headgasket would be showing bubbles in the overflow resovoir. A leaking headgasket will add combustion gasses to the cooling system and pressurize it to the point that the radiator cap pressure is reached. The excess pressure is vented out the overflow tube. Just don't leave that overflow hose blocked. If there is a head gasket leak, the pressure will continue to build and without a way out, will eventually rupture the cooling system.
As far as cleaning the radiator goes, I made up a new blowgun attachment the other night from a old piece of aluminum arrow shaft about 3/8" in diameter(2217 shaft)and about 24" long. I capped the end and drilled a 1/8" hole in the side of the tube wall about 1/2" from the end so it blows air at a 90 degree angle from the tube. I can slide this straight tube down through a small gap in the radiator shroud located at the top rear corner of the radiator on both sides. Using this access point, I can get this straight pipe down between the rear of the radiator and the front of the fan and apply air directly to the entire rear surface of the radiator without having to disassemble anything. I have been using a shopvac to clean the radiator. I used this air tube after a vacume session the other night and got a ton more debris and sand/dust out of the air passages.
sweettractors
Advertiser
Is there anything in front of the radiator intake area. I have seen some of these tractors with battery mounted in front of the radiator. --Ken Sweet
Soundguy
Old Timer
- Joined
- Mar 11, 2002
- Messages
- 51,575
- Location
- Central florida
- Tractor
- RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
You could also pressure test the cooling system.. etc.
Soundguy
Soundguy
OK. I was able to go out to work on the tractor this afternoon. I replaced the radiator cap with a 7 psi cap and did the bubble test on the overflow hose in a pitcher of water. After about 20 seconds of running I started getting bubbles coming out the overflow hose. About one a second. Nothing major, but there was bubbles. Looks like I have a leaking head gasket. I know you guys probably don't approve, but I'm going to try the Steel Seal. It's not a bunch of goop, so I don't think it will harm anything. For 50 bucks and a guarantee it can't hurt. I'll let you know how it goes.
TJ
TJ
greg_g
Super Member
- Joined
- Dec 18, 2003
- Messages
- 6,126
- Location
- Western Kentucky
- Tractor
- JD3720 Cab, 300X loader with 4-in-1 bucket
</font><font color="blueclass=small">( I replaced the radiator cap with a 7 psi cap and did the bubble test on the overflow hose in a pitcher of water. After about 20 seconds of running I started getting bubbles coming out the overflow hose. )</font>
Something doesn't sound right here TJ. Can't see where a head leak could increase pressure that fast in a cold system. With enough initial pressure to get past a properly sealed pressure cap, that is. Sounds more like
a) the pressure cap hasn't been turned all the way to the stops,
b) it's normal expansion from heat transfer via the lower radiator hose
c) a defective radiator fill neck (won't let the cap seal)
d) a radiator leak
e) any combination of the above
Guess this means you haven't pressure tested the system OR removed the radiator for cleaning yet (?)
//greg//
Something doesn't sound right here TJ. Can't see where a head leak could increase pressure that fast in a cold system. With enough initial pressure to get past a properly sealed pressure cap, that is. Sounds more like
a) the pressure cap hasn't been turned all the way to the stops,
b) it's normal expansion from heat transfer via the lower radiator hose
c) a defective radiator fill neck (won't let the cap seal)
d) a radiator leak
e) any combination of the above
Guess this means you haven't pressure tested the system OR removed the radiator for cleaning yet (?)
//greg//
RonMar
Elite Member
</font><font color="blue" class="small">( OK. I was able to go out to work on the tractor this afternoon. I replaced the radiator cap with a 7 psi cap and did the bubble test on the overflow hose in a pitcher of water. After about 20 seconds of running I started getting bubbles coming out the overflow hose))</font>
TJ, I re-read my post and realized I missed an important point with my suggestion. The radiator should be completely filled with fluid and the engine warmed up to full operating temp before you look for bubbles. On these things, if the radiator wasn't topped up, bubbles while warming up would be normal. If it bubbles after fully warm when you started with a full radiator, that air is comming from somewhere that has enough pressure behind it to force it in there. The rate of bubbles will also most likley vary with engine RPM(more RPM, more bubbles).
Since these tractors don't use a overflow/recovery tank, it is normal to have some air in the top of the radiator. When you run the engine, the fluid absorbs heat and expands. As it expands, the system pressure increases untill the radiator cap pressure is reached. When this happens, the cap opens and vents to the overflow tube to keep the system pressure within limits. If there is air on the top of the radiator, the air gets pushed out fist as pressure builds. Since there is no overflow tank, this air or fluid goes to the ground. When you shut off the engine and it cools, the fluid contracts and places the system under a vacume. There is a small check valve in the radiator cap that in the case of a radiator without a overflow tank, allows air to be sucked back into the system through the overflow pipe. If the system used an overflow tank, as it cooled the system could only draw fluid from the overflow tank and the radiator would always be full.
Since the tractor typecally runs at the same temp every time, this is no big deal as the fluid expands/contracts about the same ammount every time and pushes the air on top out and is full of fluid while operating. It then draws the same ammount of air back in when cooling and the cold fluid level stays relatively constant. This is the state these tractors run in. The radiators have a large area above the cooling passages so they can deal with this expansion/contraction.
Greg, A bubbling overflow tank or symptoms of the radiator venting/boiling over are a classic cracked head/headgasket failure in liquid cooled 2 stroke engines. This also happens in auto's, just not quite as frequently.
TJ, I re-read my post and realized I missed an important point with my suggestion. The radiator should be completely filled with fluid and the engine warmed up to full operating temp before you look for bubbles. On these things, if the radiator wasn't topped up, bubbles while warming up would be normal. If it bubbles after fully warm when you started with a full radiator, that air is comming from somewhere that has enough pressure behind it to force it in there. The rate of bubbles will also most likley vary with engine RPM(more RPM, more bubbles).
Since these tractors don't use a overflow/recovery tank, it is normal to have some air in the top of the radiator. When you run the engine, the fluid absorbs heat and expands. As it expands, the system pressure increases untill the radiator cap pressure is reached. When this happens, the cap opens and vents to the overflow tube to keep the system pressure within limits. If there is air on the top of the radiator, the air gets pushed out fist as pressure builds. Since there is no overflow tank, this air or fluid goes to the ground. When you shut off the engine and it cools, the fluid contracts and places the system under a vacume. There is a small check valve in the radiator cap that in the case of a radiator without a overflow tank, allows air to be sucked back into the system through the overflow pipe. If the system used an overflow tank, as it cooled the system could only draw fluid from the overflow tank and the radiator would always be full.
Since the tractor typecally runs at the same temp every time, this is no big deal as the fluid expands/contracts about the same ammount every time and pushes the air on top out and is full of fluid while operating. It then draws the same ammount of air back in when cooling and the cold fluid level stays relatively constant. This is the state these tractors run in. The radiators have a large area above the cooling passages so they can deal with this expansion/contraction.
Greg, A bubbling overflow tank or symptoms of the radiator venting/boiling over are a classic cracked head/headgasket failure in liquid cooled 2 stroke engines. This also happens in auto's, just not quite as frequently.
greg_g
Super Member
- Joined
- Dec 18, 2003
- Messages
- 6,126
- Location
- Western Kentucky
- Tractor
- JD3720 Cab, 300X loader with 4-in-1 bucket
</font><font color="blue" class="small">( Greg, A bubbling overflow tank or symptoms of the radiator venting/boiling over are a classic cracked head/headgasket failure in liquid cooled 2 stroke engines.)</font>
I think you meant 4 stroke engines Ron, and I also think you might consider re-reading my previous response to Adam as well.
I readily agree with your point about visual cues to "a classic cracked head/headgasket failure" - on an engine at or over operating temperature. But the impression I got from Adam's post, was that he observed 1 bubble per second through the overflow hose of an otherwise cold engine - and one with a reportedly brand new radiator cap at that.
I don't believe enough ground has been covered to accept "cylinder head problem" as the final diagnosis just yet. As such, I believe it's also premature to arbitrarily start pouring in dubious "remedies".
//greg//
I think you meant 4 stroke engines Ron, and I also think you might consider re-reading my previous response to Adam as well.
I readily agree with your point about visual cues to "a classic cracked head/headgasket failure" - on an engine at or over operating temperature. But the impression I got from Adam's post, was that he observed 1 bubble per second through the overflow hose of an otherwise cold engine - and one with a reportedly brand new radiator cap at that.
I don't believe enough ground has been covered to accept "cylinder head problem" as the final diagnosis just yet. As such, I believe it's also premature to arbitrarily start pouring in dubious "remedies".
//greg//
Wayne_Freeman
Gold Member
When this happened to my Jinma the symptoms were: slow loss of radiator liquid, slow overheating of the engine (depending on ambient temp it might go an hour before red lining) and finally with the radiator cap off and engine started you had a very active bubbling as seen from the top of the radiator. Now I am sure there might be some bubbling anyway but this was REALLY BUBBLING! One bubble per second in the overflow tube is not what I observed and would not be a proper diagnosis. I think if these three symptoms fit and you have tried the other remedies then you probably will have to replace the head gasket. It really is not that big of a job!
RonMar
Elite Member
</font><font color="blue" class="small">( I think you meant 4 stroke engines Ron)</font>
No, I meant 2 strokes, I said autos(4 strokes) after that to include them as well. It is less common on auto engines probably because they typically have a better head/block interface. It is fairly common on liquid cooled 2 strokes(less robust union, run harder).
</font><font color="blue" class="small">( But the impression I got from Adam's post, was that he observed 1 bubble per second through the overflow hose of an otherwise cold engine)</font>
I got the same impression, that is why I posted again. I realized I had forgotten to cover that part in my initial post. I also missed the word Cold in your response, sorry.
This symptom can show itself in cold engines also but it is usually pretty evident what it is. I bought a 88 Toyota 4X4 last year from some folks for cheap. Great body/running gear but it runs rough and "Keeps Overheating". They took it to a mechanic and he said it had a cracked head and gave them a pretty expensive repair estimate so they decided to sell it "as-is"(I don't think the mechanic even pulled the head). I got it home and did a cold compression test and the first 2 cylinders were chained together and to the cooling system. After cranking it for the test, a hissing could be heard, comming from the pressurized cooling system as the air pushed in from the cylinders escaped. I inspected the head and found nothing wrong and reassembled it with a new gasket. It has been running fine for about 8 months now.
</font><font color="blue" class="small">( I don't believe enough ground has been covered to accept "cylinder head problem" as the final diagnosis just yet. As such, I believe it's also premature to arbitrarily start pouring in dubious "remedies".)</font>
I agree with this 100%, but since this is such a simple thing to rule out from the beginning(look for bubbles in a container of water) that it would be a good thing to look at, especially since he said it had a possibly severe overheat 6 months ago due to loosing a fan belt. No bubbles at temp, the problem lies elsewhere(clogged radiator water or air passages, pump problem ect...). I am not a fan of "Dubious remedies" or "Mechanic in a can" at any time.
No, I meant 2 strokes, I said autos(4 strokes) after that to include them as well. It is less common on auto engines probably because they typically have a better head/block interface. It is fairly common on liquid cooled 2 strokes(less robust union, run harder).
</font><font color="blue" class="small">( But the impression I got from Adam's post, was that he observed 1 bubble per second through the overflow hose of an otherwise cold engine)</font>
I got the same impression, that is why I posted again. I realized I had forgotten to cover that part in my initial post. I also missed the word Cold in your response, sorry.
This symptom can show itself in cold engines also but it is usually pretty evident what it is. I bought a 88 Toyota 4X4 last year from some folks for cheap. Great body/running gear but it runs rough and "Keeps Overheating". They took it to a mechanic and he said it had a cracked head and gave them a pretty expensive repair estimate so they decided to sell it "as-is"(I don't think the mechanic even pulled the head). I got it home and did a cold compression test and the first 2 cylinders were chained together and to the cooling system. After cranking it for the test, a hissing could be heard, comming from the pressurized cooling system as the air pushed in from the cylinders escaped. I inspected the head and found nothing wrong and reassembled it with a new gasket. It has been running fine for about 8 months now.
</font><font color="blue" class="small">( I don't believe enough ground has been covered to accept "cylinder head problem" as the final diagnosis just yet. As such, I believe it's also premature to arbitrarily start pouring in dubious "remedies".)</font>
I agree with this 100%, but since this is such a simple thing to rule out from the beginning(look for bubbles in a container of water) that it would be a good thing to look at, especially since he said it had a possibly severe overheat 6 months ago due to loosing a fan belt. No bubbles at temp, the problem lies elsewhere(clogged radiator water or air passages, pump problem ect...). I am not a fan of "Dubious remedies" or "Mechanic in a can" at any time.