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2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
L98 water flow direction
Just curious,,,which direction does the water flow thru the motor? Here are my guesses....
in at top of radiator, out at bottom
water pump into motor (bottom to top)
out thru: intake manifold, block to oil cooler and back of manifold
manifold goes thru TB, then over to heater, then back to water pump/cooler
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Sounds like I had it right. I raised the question for two reasons. I already performed the TB bypass (by removing that part of the IAC housing). Now, I'm also looking at removing the stock oil cooler.
I was trying to think of a more elegant routing for coolant lines but don't think there is one. Specifically, the one exiting the front of the intake manifold is what I'm looking at.
Sounds like I had it right. I raised the question for two reasons. I already performed the TB bypass (by removing that part of the IAC housing). Now, I'm also looking at removing the stock oil cooler.
I was trying to think of a more elegant routing for coolant lines but don't think there is one. Specifically, the one exiting the front of the intake manifold is what I'm looking at.
Put a plug in the block next to the oil cooler to replace the fitting. Plug wherever the other end of the cooler goes.
I was trying to think of a more elegant routing for coolant lines but don't think there is one. Specifically, the one exiting the front of the intake manifold is what I'm looking at.
Can't help with the oil cooler...myself I always thought those were more trouble than they were worth.
I've got a super long hose (~7") for the front of the intake back to the heater core. I actually routed it straight out of the intake nipple and it runs up along under the MAF ducting then does a 180* turn just in front of the radiator before returning under the AC lines back to the heater core. Looks a little funky from a stock setup but it is not bad....there is no clearance issues. I'll snap a pick in the next day or so and you can get a visual.
Well yeah.... I was looking at hose routing to get water out of the front manifold. Trying to go down, over to the heater and back.
Not all L98s came with oil coolers. Water goes from the radiator, to the block, through the heads, into the inake, through the thermostat, back into the radiator. You don't have to worry about getting water from the manifold back into the block.
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Originally Posted by 383vett
Not all L98s came with oil coolers. Water goes from the radiator, to the block, through the heads, into the inake, through the thermostat, back into the radiator. You don't have to worry about getting water from the manifold back into the block.
What about the heater core though? A feed and return line still needs to go to it. It sounds like the return line is the one that connects to the water pump. Where would you tap a feed line -- if the front manifold nipple were plugged?
(Getting it from the bottom of the block would be an interesting thought. Though going up/around headers might not be that "fun".)
Where do the heater hoses connect on non-cooler cars?
Last edited by GREGGPENN; May 7, 2010 at 01:32 PM.
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Where do the heater hoses connect on non-cooler cars?
'89:
Upper hose (larger diameter hose with the "T" splice which feeds the intake riser passage by the EGR) for the heater connects to the output side of the H20 pump and the lower goes to the front of the intake.
Last edited by engle1147; May 8, 2010 at 12:27 PM.
Reason: Had the upper hose as being the smaller hose
Just curious,,,which direction does the water flow thru the motor?
Its been awhile since I've seen a oil cooler installed but here's the rest of the deal.
L98:
For the most part the GEN 1 small block sucks from bottom of the radiator to the waterpump and coolant is pumped into the front of the block and around the cylinders. Coolant continues to migrate under pressure through the holes in the heads and then travels along to collect at the front of each cylinder head to the front of the intake. It continues through to the front of the intake manifold. Then once up to temp the thermostat opens and coolant flows directly back to the radiator. There is a coolant bypass built into the waterpump which feeds the heater core and the attached hoses such as the heat riser and TB the coolant for these ends up in the front of the intake manifold as well.
Lower hose for the heater connects to the output side of the H20 pump and the upper goes to the front of the intake.
WP is return (suction) side of heater circuit.
Hot water from front of intake ( hottest part ) goes to heater core returning to pump .Your flow path has coolest water from bottom of radiator going to heater core
You sure about that? Another member said his oil temps were a mere 5-10 degrees higher w/o the cooler.
That might be his experience
After owning my cars for 10 years, I know normal operating temps and that is the difference I see with / without cooler operation
Originally Posted by GREGGPENN
What do you think of the idea of running the heater hose feed line thru the A/C bracket with it's return line?
Won't fit through the hole with other hose but will fit between A/c bracket and block to run parallel with return hose
WP is return (suction) side of heater circuit.
Hot water from front of intake ( hottest part ) goes to heater core returning to pump .Your flow path has coolest water from bottom of radiator going to heater core
Anyone think the oil cooler is worth a diddly-squat?
I use the oil cooler to heat up the oil on my bracket car. After 45 minutes or an hour between the first rounds, my oil temperature will be well below 150. The warm water circulating through the cooler helps raise the oil temperature before staging. With a 1/4 mile run, oil that is too hot is not an issue with me. Too cold is.
1988 vette coup.....Attached are a few picts of old water pump I removed and replaced due to leaking gasket as well as picts of the heater core inlet-outlet ports....
QUESTION ...Looking at the heater port picts,
1)....does coolant flow intothe top of the heater core and out the bottom OR OR OR OR OR
2)....into the bottom and out the top?
(notice the orig configuration of hoses where the top hose has a "T" out of the side of the hose and going to the block at the back - hard to see but, believe it is the block and not intake).
L98 water flow direction
