Hey Everyone,
The AMC 360 in my CJ 8 is giving me a hot problem. It's got new hoses,
belts, 4-core radiator, flex-fan and stock-replacement water pump. I had in a
195 t-stat for winter heat, and it's been getting hot lately. The mech. temp
gauge would wander up to 210, and it's barely cracked the 70's here in PA.
Even cruising at highway speeds it would barely go below 200. I did some
checking, and with the engine running and rad cap off, there's barely any
coolant flowing. Crank the throttle and some flows, but not much.
Today i put in a cold t-stat (160) and drained the coolant, put in Prestone's
rad flush, and filled with water as per the bottle. I drained and refilled
with water three times. The last time i even used the flush-kit with a garden
hose to pump fresh water throughout the system, and it all came out clean. I
was hoping to see some crud from a blocked passage or something. I put the
coolant back in with a new bottle of Water Wetter. Still not much flowing.
The gauge is a little lower, but when i hold the throttle, the gauge climbs
again. The fan is good, you can feel plenty of air pulling through the rad.
I've worked in the parts business long enough to know "new" parts can be bad
sometimes. Does this sound like a bad water pump?

Thanks,
Don W

'82 CJ8 Scrambler
AMC 360
T/F 727
Dana 300
One-piece model 20 rear
Dana 30 front, upgraded to 6-bolt caliper and Warn hubs, awaiting locker
2" shackle lift/reversal
2" lift springs of unknown origin
33" Mickey's

And it finally runs!!!!!

 

Hmmm...

My first guess would be a polished up fan belt.

The water pump and alternator take some HP to spin them up and I find
Jeeps have a nasty tendency to polish up v-belts from mud puddles. Mud
= liquid sandpaper.

I have a fast test for it. On a cold off engine, grab the alternator
pulley and see if you can hand slip it under the belt tension. If you
can, the belt is dead and the waterpump will slip too. You can grab the
pump pulley and see if you can hand slip that too.

You are 'not' supposed to be able to slip either. When I turn the
alternator pulley, the engine should turn over.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Don Wallish wrote:
>
> Hey Everyone,
> The AMC 360 in my CJ 8 is giving me a hot problem. It's got new hoses,
> belts, 4-core radiator, flex-fan and stock-replacement water pump. I had in a
> 195 t-stat for winter heat, and it's been getting hot lately. The mech. temp
> gauge would wander up to 210, and it's barely cracked the 70's here in PA.
> Even cruising at highway speeds it would barely go below 200. I did some
> checking, and with the engine running and rad cap off, there's barely any
> coolant flowing. Crank the throttle and some flows, but not much.
> Today i put in a cold t-stat (160) and drained the coolant, put in Prestone's
> rad flush, and filled with water as per the bottle. I drained and refilled
> with water three times. The last time i even used the flush-kit with a garden
> hose to pump fresh water throughout the system, and it all came out clean. I
> was hoping to see some crud from a blocked passage or something. I put the
> coolant back in with a new bottle of Water Wetter. Still not much flowing.
> The gauge is a little lower, but when i hold the throttle, the gauge climbs
> again. The fan is good, you can feel plenty of air pulling through the rad.
> I've worked in the parts business long enough to know "new" parts can be bad
> sometimes. Does this sound like a bad water pump?
>
> Thanks,
> Don W
>
> '82 CJ8 Scrambler
> AMC 360
> T/F 727
> Dana 300
> One-piece model 20 rear
> Dana 30 front, upgraded to 6-bolt caliper and Warn hubs, awaiting locker
> 2" shackle lift/reversal
> 2" lift springs of unknown origin
> 33" Mickey's
>
> And it finally runs!!!!!

 

Hmmm...

My first guess would be a polished up fan belt.

The water pump and alternator take some HP to spin them up and I find
Jeeps have a nasty tendency to polish up v-belts from mud puddles. Mud
= liquid sandpaper.

I have a fast test for it. On a cold off engine, grab the alternator
pulley and see if you can hand slip it under the belt tension. If you
can, the belt is dead and the waterpump will slip too. You can grab the
pump pulley and see if you can hand slip that too.

You are 'not' supposed to be able to slip either. When I turn the
alternator pulley, the engine should turn over.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Don Wallish wrote:
>
> Hey Everyone,
> The AMC 360 in my CJ 8 is giving me a hot problem. It's got new hoses,
> belts, 4-core radiator, flex-fan and stock-replacement water pump. I had in a
> 195 t-stat for winter heat, and it's been getting hot lately. The mech. temp
> gauge would wander up to 210, and it's barely cracked the 70's here in PA.
> Even cruising at highway speeds it would barely go below 200. I did some
> checking, and with the engine running and rad cap off, there's barely any
> coolant flowing. Crank the throttle and some flows, but not much.
> Today i put in a cold t-stat (160) and drained the coolant, put in Prestone's
> rad flush, and filled with water as per the bottle. I drained and refilled
> with water three times. The last time i even used the flush-kit with a garden
> hose to pump fresh water throughout the system, and it all came out clean. I
> was hoping to see some crud from a blocked passage or something. I put the
> coolant back in with a new bottle of Water Wetter. Still not much flowing.
> The gauge is a little lower, but when i hold the throttle, the gauge climbs
> again. The fan is good, you can feel plenty of air pulling through the rad.
> I've worked in the parts business long enough to know "new" parts can be bad
> sometimes. Does this sound like a bad water pump?
>
> Thanks,
> Don W
>
> '82 CJ8 Scrambler
> AMC 360
> T/F 727
> Dana 300
> One-piece model 20 rear
> Dana 30 front, upgraded to 6-bolt caliper and Warn hubs, awaiting locker
> 2" shackle lift/reversal
> 2" lift springs of unknown origin
> 33" Mickey's
>
> And it finally runs!!!!!

 

Hmmm...

My first guess would be a polished up fan belt.

The water pump and alternator take some HP to spin them up and I find
Jeeps have a nasty tendency to polish up v-belts from mud puddles. Mud
= liquid sandpaper.

I have a fast test for it. On a cold off engine, grab the alternator
pulley and see if you can hand slip it under the belt tension. If you
can, the belt is dead and the waterpump will slip too. You can grab the
pump pulley and see if you can hand slip that too.

You are 'not' supposed to be able to slip either. When I turn the
alternator pulley, the engine should turn over.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Don Wallish wrote:
>
> Hey Everyone,
> The AMC 360 in my CJ 8 is giving me a hot problem. It's got new hoses,
> belts, 4-core radiator, flex-fan and stock-replacement water pump. I had in a
> 195 t-stat for winter heat, and it's been getting hot lately. The mech. temp
> gauge would wander up to 210, and it's barely cracked the 70's here in PA.
> Even cruising at highway speeds it would barely go below 200. I did some
> checking, and with the engine running and rad cap off, there's barely any
> coolant flowing. Crank the throttle and some flows, but not much.
> Today i put in a cold t-stat (160) and drained the coolant, put in Prestone's
> rad flush, and filled with water as per the bottle. I drained and refilled
> with water three times. The last time i even used the flush-kit with a garden
> hose to pump fresh water throughout the system, and it all came out clean. I
> was hoping to see some crud from a blocked passage or something. I put the
> coolant back in with a new bottle of Water Wetter. Still not much flowing.
> The gauge is a little lower, but when i hold the throttle, the gauge climbs
> again. The fan is good, you can feel plenty of air pulling through the rad.
> I've worked in the parts business long enough to know "new" parts can be bad
> sometimes. Does this sound like a bad water pump?
>
> Thanks,
> Don W
>
> '82 CJ8 Scrambler
> AMC 360
> T/F 727
> Dana 300
> One-piece model 20 rear
> Dana 30 front, upgraded to 6-bolt caliper and Warn hubs, awaiting locker
> 2" shackle lift/reversal
> 2" lift springs of unknown origin
> 33" Mickey's
>
> And it finally runs!!!!!

 

Hmmm...

My first guess would be a polished up fan belt.

The water pump and alternator take some HP to spin them up and I find
Jeeps have a nasty tendency to polish up v-belts from mud puddles. Mud
= liquid sandpaper.

I have a fast test for it. On a cold off engine, grab the alternator
pulley and see if you can hand slip it under the belt tension. If you
can, the belt is dead and the waterpump will slip too. You can grab the
pump pulley and see if you can hand slip that too.

You are 'not' supposed to be able to slip either. When I turn the
alternator pulley, the engine should turn over.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Don Wallish wrote:
>
> Hey Everyone,
> The AMC 360 in my CJ 8 is giving me a hot problem. It's got new hoses,
> belts, 4-core radiator, flex-fan and stock-replacement water pump. I had in a
> 195 t-stat for winter heat, and it's been getting hot lately. The mech. temp
> gauge would wander up to 210, and it's barely cracked the 70's here in PA.
> Even cruising at highway speeds it would barely go below 200. I did some
> checking, and with the engine running and rad cap off, there's barely any
> coolant flowing. Crank the throttle and some flows, but not much.
> Today i put in a cold t-stat (160) and drained the coolant, put in Prestone's
> rad flush, and filled with water as per the bottle. I drained and refilled
> with water three times. The last time i even used the flush-kit with a garden
> hose to pump fresh water throughout the system, and it all came out clean. I
> was hoping to see some crud from a blocked passage or something. I put the
> coolant back in with a new bottle of Water Wetter. Still not much flowing.
> The gauge is a little lower, but when i hold the throttle, the gauge climbs
> again. The fan is good, you can feel plenty of air pulling through the rad.
> I've worked in the parts business long enough to know "new" parts can be bad
> sometimes. Does this sound like a bad water pump?
>
> Thanks,
> Don W
>
> '82 CJ8 Scrambler
> AMC 360
> T/F 727
> Dana 300
> One-piece model 20 rear
> Dana 30 front, upgraded to 6-bolt caliper and Warn hubs, awaiting locker
> 2" shackle lift/reversal
> 2" lift springs of unknown origin
> 33" Mickey's
>
> And it finally runs!!!!!