Fuel Pump pressure gauge set up

[MrMarty51]

The one thing I have noticed since installing the cooling upgrade on my 95 is it seems to take longer to have heat in the cab! not sure if this was due to the equal flow pump, but the 93 which is still styling the factory style wp gets it's heater warm in maybe 5 minutes where my 95 takes at least 10 minutes to feel any heat from the vents!

Does Your 95 have the PTO option wired to a switch ?
A cummins diesel pickup I once had, it would never throw warm air with enjun at idle.
This 2000 was the same until I wired in the PTO option and now can step the idle up.
Bout five minits and it is blowing toasty and warm.

 

[dbrannon79]

Does Your 95 have the PTO option wired to a switch ?
A cummins diesel pickup I once had, it would never throw warm air with enjun at idle.
This 2000 was the same until I wired in the PTO option and now can step the idle up.
Bout five minits and it is blowing toasty and warm.

Yes, I have it installed. most of the time I don't use it simply because I hate cranking it up with the remote start cold and the high idle switch on! It does however idle it's self up to about 900 without the switch turned on when it's below 40 degrees.

But even once warmed up the heater in the 95 is just warm. on the 93 when it's fully warm it will burn you out of the cab!! someone here was talking about this and the differences between trucks, no physical differences and all the same hose routing, just some engines will warm up quicker than others. my two might be a prime example.

 

[MrMarty51]

Yes, I have it installed. most of the time I don't use it simply because I hate cranking it up with the remote start cold and the high idle switch on! It does however idle it's self up to about 900 without the switch turned on when it's below 40 degrees.

But even once warmed up the heater in the 95 is just warm. on the 93 when it's fully warm it will burn you out of the cab!! someone here was talking about this and the differences between trucks, no physical differences and all the same hose routing, just some engines will warm up quicker than others. my two might be a prime example.

I also have that restrictor fitting, from Leroy Diesel, installed on the coolant pump bypass fitting.
Restricts some of the coolant from flowing straight back to the radiator.
That might help with internal temps too.

 

[dbrannon79]

Where does this fitting go? on the crossover going to the heater core or underneath between the crossover to the pump? both my trucks use the single t-stat crossover with the t-stat that has the block-off plate on bottom. when I pulled the crossover on the 93 (has the good heater) both fitting were just a hose bib iirc.

I never checked but with the upgraded WP on the 95 I might need to restrict the flow some going back into the radiator from the heater core. the 95 does have a water valve inline on the hose from the heater core going into the radiator. I wonder if I close it maybe half way if that would make a difference.

 

[MrMarty51]

Where does this fitting go? on the crossover going to the heater core or underneath between the crossover to the pump? both my trucks use the single t-stat crossover with the t-stat that has the block-off plate on bottom. when I pulled the crossover on the 93 (has the good heater) both fitting were just a hose bib iirc.

I never checked but with the upgraded WP on the 95 I might need to restrict the flow some going back into the radiator from the heater core. the 95 does have a water valve inline on the hose from the heater core going into the radiator. I wonder if I close it maybe half way if that would make a difference.

This is on the twin T~Stat cross over.
On My truck the fitting between the WP and the T~Stat housing is removed and the restricted fitting installed.
I tried to remove the fitting from the cross over and it was mighty tight so I removed the fitting from the WP.
Now I nust need to remember to change fittings if ever I have to install a new WP.

The sales page does not mention of it is specifically for the twin stat cross over.

Leroy Diesel

leroydiesel.com

 

[Will L.]

I also have that restrictor fitting, from Leroy Diesel, installed on the coolant pump bypass fitting.
Restricts some of the coolant from flowing straight back to the radiator.
That might help with internal temps too.

NO- bad description or misunderstanding here.

Without the restriction fitting AND a non bybass blocking thermostat, which there are some single and all dual thermostat crossovers without block off plate:

The hose that goes from the crossover back down to the waterpump is unrestricted so all that water goes from waterpump to block around cylinders then at the rear go up to the heads. Go foreward across the head and through the crossover. From there it is ready tomgl to the radiator but thermostat is closed. So it goes through the hose to the waterpump and meeps recirculating.

When the thermostat opens up about 3/4 of it goes to the radiator and 1/4 of it continues to go through that short hose back to the waterpump and keeps recirculating. Your 200° coolant goes to the radiator and gets cooled to say 170°, goes up the lower radiator hose and into the waterpump where it mixes with 25% water at OVER 200°.
For cooling purposes it is a horrible design- outright stupid. Thats why the block off thermostat was created. The water has to circulate in the engine from the mechanical water pump- so non bypassing thermostat has to have a circulation route or it will cavitate and aerate the water. Ever look at the backing plate for the waterpump and it’s all “chewed up” or “divits of metal missing”? That is from cavitation. Even with the stupid recirculating hose and no bypass that hose being less than half the size means a restriction in flow causing cavitation.

The restrictor fitting does NOT restrict water from going to the radiator. It restricts water from recirculating in the engine and forces it to the radiator so that a larger percentage of the water gets cooled off, and there is less fully heated water in the pump to mix in and heat up the cool water.

There is a negative effect - the backing plate will get pitting a little faster but that is a minor issue compared to ruining the heads, pistons, rings, and block. I experimented with silicone to smooth the pitted plate- bad choice. The cavitation gets strips is clean and now debris is in the system. Same for powder coat- don’t do it.


As to Leroy not mentioning twin stat crossover- that is because the original restriction fitting was done on engines with single stat crossover that wasn’t block off aka bypass style thermostats.
The creation of the dual thermostat housing not being bypass is an absurd error.
Many people learned to replace the dual crossover for the older single with bypass unit. The problem is the accessories get in the way for most - this is why the rare 1996 part is so desirable- single stat crossover that fits the newer trucks.

Look at the block off option link in my signature for better cooling but no rare 96 crossover handy… but if your heat is under control, don’t bother.

When wanting the truck to heat up faster- the recirculating coolant is desirable. But this is simply the thermostat stays closed and it recirculates all except the thermostat weep hole. And since there is one per stat- the dual one does a worse job.
A higher opening temp of the thermostat(s) helps to force hotter recirculating temp
So I have heard of guys with duals running 1-180 & 1-195 attempting a happy medium for winter time.

Most the guys who want heat and longer engine life buy a comfort heater from Wabasto. Make the engine run cool and live long, burn a little extra fuel for cozy factor.

 

[MrMarty51]

NO- bad description or misunderstanding here.

Without the restriction fitting AND a non bybass blocking thermostat, which there are some single and all dual thermostat crossovers without block off plate:

The hose that goes from the crossover back down to the waterpump is unrestricted so all that water goes from waterpump to block around cylinders then at the rear go up to the heads. Go foreward across the head and through the crossover. From there it is ready tomgl to the radiator but thermostat is closed. So it goes through the hose to the waterpump and meeps recirculating.

When the thermostat opens up about 3/4 of it goes to the radiator and 1/4 of it continues to go through that short hose back to the waterpump and keeps recirculating. Your 200° coolant goes to the radiator and gets cooled to say 170°, goes up the lower radiator hose and into the waterpump where it mixes with 25% water at OVER 200°.
For cooling purposes it is a horrible design- outright stupid. Thats why the block off thermostat was created. The water has to circulate in the engine from the mechanical water pump- so non bypassing thermostat has to have a circulation route or it will cavitate and aerate the water. Ever look at the backing plate for the waterpump and it’s all “chewed up” or “divits of metal missing”? That is from cavitation. Even with the stupid recirculating hose and no bypass that hose being less than half the size means a restriction in flow causing cavitation.

The restrictor fitting does NOT restrict water from going to the radiator. It restricts water from recirculating in the engine and forces it to the radiator so that a larger percentage of the water gets cooled off, and there is less fully heated water in the pump to mix in and heat up the cool water.

There is a negative effect - the backing plate will get pitting a little faster but that is a minor issue compared to ruining the heads, pistons, rings, and block. I experimented with silicone to smooth the pitted plate- bad choice. The cavitation gets strips is clean and now debris is in the system. Same for powder coat- don’t do it.


As to Leroy not mentioning twin stat crossover- that is because the original restriction fitting was done on engines with single stat crossover that wasn’t block off aka bypass style thermostats.
The creation of the dual thermostat housing not being bypass is an absurd error.
Many people learned to replace the dual crossover for the older single with bypass unit. The problem is the accessories get in the way for most - this is why the rare 1996 part is so desirable- single stat crossover that fits the newer trucks.

Look at the block off option link in my signature for better cooling but no rare 96 crossover handy… but if your heat is under control, don’t bother.

When wanting the truck to heat up faster- the recirculating coolant is desirable. But this is simply the thermostat stays closed and it recirculates all except the thermostat weep hole. And since there is one per stat- the dual one does a worse job.
A higher opening temp of the thermostat(s) helps to force hotter recirculating temp
So I have heard of guys with duals running 1-180 & 1-195 attempting a happy medium for winter time.

Most the guys who want heat and longer engine life buy a comfort heater from Wabasto. Make the engine run cool and live long, burn a little extra fuel for cozy factor.

HA, I was ALLLLLL WRONG.

 

[Will L.]

Asking and speaking up is how we learn my friend-
That and talking back to our moms… I learned a lot and learned it fast doing that! Only took once! Haha

 

[dbrannon79]

So.... out of curiosity. on my 95 it has the single stat with the block off plate but no matter if it's got a 180 or 195 stat, the engine has always not had a good heater in the winter nor does it warm up like the 93 does. currently the 95 has a 180 stat only because I don't like the 195 as it will maintain too close to 200 for my liking. yes the heater does get warmer with the 195 but still not like the 93.

would it make any sense to install the restrictor valve in combination with it having the block off stat installed to allow it to warm up sooner in the winter while keeping the 180 stat installed?

I cannot remember as of current, but if memory serves me right, the 93 also has a 180 stat too. I think I checked that when I replaced the crossover due to it leaking on the block. when I pulled it off thinking I would just replace gaskets I had found that one of the bolt hole ears that hold it to the block had been broken off and re-welded. there was a spare in with all the parts I got with that truck so I used it on the truck.


side note: I think there was another crossover within all the parts that uses a single stat but faces toward the engine like the 96+ does, but it's missing the stat housing end. I will need to dig back though the parts hord and make sure if that was what I was looking at.

 

[Will L.]

No, adding the restrictor won’t help that.

Have you flushed the heater core?
Does it get really good airflow from fan?
Are you 100% that the blend door is 100% closed?

 

[dbrannon79]

No, adding the restrictor won’t help that.

Have you flushed the heater core?
Does it get really good airflow from fan?
Are you 100% that the blend door is 100% closed?

heater core replaced not long after buying the truck.
fan is decent and evap core area was cleaned of leaves...
when I replaced the dash I replaced the section with the doors, old ones were broken.

All said, heater core not being factory and from the auto parts house might be an issue