Shinniu sn25 running hot

[Shenniu SN25]

Replaced head gasket, unclogged the injection pump,adjusted the timing and it's up and running. Surprised how much power this thing has. Just got to solve the running hot issue... Anyone know what the thermostat should open up at I'm thinking it should open around 180 or 190. Forgot to add replaced radiator cap with 10# cap wasn't sure what the oem was.

 

[greg_g]

Thermostat is typically either 72C (~162F) or 80C (176F). Cap is typically 0.3 (~4psi) or 0.5 bar (~7 psi).

//greg//

 

[Shenniu SN25]

Ok so I took the thermostat out ant still runs hot is it possible it's just moving the water to fast, not getting a chance to cool the water in the radiator before recirculating it... Checked the pressure in the radiator it builds 20 psi.

 

[greg_g]

Naw, removing the thermostat on an otherwise healthy diesel usually results in the opposite; running too cold. And 20psi actually sounds high. Remove the cap, start the engine, look inside the radiator. See any bubbling?

//greg//

 

[Gene :^)]

Diesel at idle usually cools itself down. Only generates heat when working. Did it reach 20psi before it even got hot? Normally any psi comes from water expanding by heat, so if pressure came up faster then it may be coming from elsewhere (like combustion).

Get this: Test Tools Inc. - Combustion Leak Block Tester, Test for Blown Head Gasket and see if your head gasket is still leaking. Most good auto parts stores or tool trucks have this tool if you don't want to wait for it in the mail. Mine was about $30 and can be used many times over.

If head gasket passes all tests, I would look at the injection. When you say it has a LOT of power, it sounds like you may be over fueling. I am not sure what effect timing has on heat but it could be an issue too. At idle does it seem to knock and bang (diesel sound) more than normal? The more you advance it the harder the knocks and bangs at idle, the more you ****** it the smoother it idles but more smoke and makes your eyes water.

Gene :^)

 

[RonMar]

If it is pushing combustion gas into the coolant, this could be warming the temp sensor artificially. You could also confirm running temp with an IR thermometer... You shouldn't see 20 PSI on the cooling system unless it was at full op temp...

 

[Shenniu SN25]

Builds 20 psi after it warms up when cold i see around 5 to 10 psi. I let it run a little longer with the gauge on it and it still seems to build past 20 then it just bypasses through the overfill hose i got plugged off to do the check. Thinking it may be the head gasket still leaking. When I first got it running it knocked very bad adjusted timing back now it runs smooth and starts easy. Head gaskets seem to be a big problem with these tractors any suggestions for getting it to hold this time. I used loctite 271 on the threads and a bottle of the silver stop leak on this install. What should the head bolts be torqued to?

 

[greg_g]

I'm not sure if I understood you correctly, but you cannot "repair" a blown head gasket. It must be replaced. And since most head gaskets nowadays are laminated with metal cylinder inserts, nothing other than clean head and block surfaces is required. Don't know anyone who'd advocate LokTite on head bolts. If they keep backing out on you, they're simply worn out. The solution is to replace them

//greg//

 

[Shenniu SN25]

The head gasket is leaking I can see it bubbling out around the head. It's an extremely cheap looking head gasket it has no steel reinforcements, you can see what appears to be paper or gasket material sandwiched between two sheets of copper looking at the gasket the old one was the same way. It cost 10 bucks... I'm thinking I didn't torq it tight enough. Any specs for this? I bought two when I found the gasket figured it would be hard to find another, so if this one has blown out I got another one. I read on another thread you should use something to seal the head bolts that's why I used loctite.

 

[jonyyuma]

Have you had the head tested for cracks? Then it needs to be checked for flatness and trueness.. what did you use for a guide on torque values for the headbolts?