englundjd

ok so ive been fighting a few water leaks on my car and i think i have them all fixed but im not sure... i cant tell if im loosing water or not. If i look in the radiator when the car is off (and cold) i see no antifreeze, but if i look in the reservor when its ~190* the little plastic strip indicates that it is full... is it low? or is my car as confused as me? lol


On a different note i picked up a couple LT1 blocks for cheap, both virgin bore 2 bolt mains, one of them had a short block in it with 2 spun bearings. the crank shaft will need machining but should be reusable... now i want to build a 400rwhp/tq engine and later on i might add a small shot of n2o. Will the stock crank shaft hold up and be reliable or should i get something forged?

I also want to know if there is any other good head porters and custom cam grinders other then LE and AI ... just exploring my options

Thanks

LTX

i had same issue, you fill it when the car is off till you see all the coolant top off. make sure all the air bubbles are out! and stock cranks are strong, i havent seen one break. a few guys on here are running 700hp with the stock crank!

englundjd

yea i usually fill it when its off and cold... and then the next day it will be down again

haha cool then i guess i wont need to buy a new crankshaft

the_merv

iTrader: (88)

Make sure it's not eating it up..is it burning it?

lt1slowz28

I chased an issue like this and it wouldnt show any leaks nor signs other than random missing coolant.... temps were always fine and never a drop anywhere.


turned out to be the radiator caps seal, it was old and the rubber lost all elasticity... guessing it all slowly went onto the road somewhere, but when cooled down while idling it would seal back up. worth a shot. try it out

FAD2BLK93

Is the heater core leaking? Check ur passenger floor board.

englundjd

Well there is no leaks inside the car, its got 4000 miles on a totally new engine ... i would hope its not a head gasket. The cap is not leaking i have an electric water pump and ive been under the hood with the engine on and hot. the cap doesnt leak.

lt1slowz28

check to see if your thermostat works (put it in a pot of boiling water)... I know it sounds crazy but I went through hell not long ago with all of the troubles with one that would open one side but not the other of the thermostat...


https://ls1tech.com/forums/lt1-lt4-m...king-dave.html

ken125

iTrader: (3)

Any steam from exhaust thats noticeable? Also small leaks that leak into the cylinder can be very hard to find without removing the heads. You can check all the plugs to see if any look odd, that could indicated a leak for that cylinder. Try a compression and leakdown test. Good luck!

SS RRR

iTrader: (2)

Your tests aren't definitive. What does the reservoir read when the coolant is completely cold?
What I would do is when the coolant is completely cold, make sure the radiator and reservoir are at their proper levels, run engine to operating temp and then check reservoir level. Relieve pressure from cooling system and check radiator level. You can also run a pressure test by renting a pressure tester from most any parts store.
If you are sure all air is out of the cooling system then one possibility is a leak in the return line from the reservoir to the radiator. Once coolant cools down and pressure subsides, coolant returns to the radiator. If there is a leak in the return line it will inject air into radiator and coolant will remain in reservoir.

englundjd

well last night me and a mechanic checked one last time for any noticable leaks... nothin... the exhaust didn't smell like antifreeze at all. checked everything before we started looking ( engine cold ) and it was all up, checked reservor after we checked for leaks ( engine hot ). i do wonder if i have a small headgasket leak that only rears its head once in a while?

SS RRR; im going to check that hose thats a good idea

quik95lt1

iTrader: (7)

as for the engine......a two bolt with a small shot <100 and under 6500rpm with a stock crank will be fine no issue there.......as for the coolant issue try replacing the radiator cap........i had that issue on mine the cap seal went bad so when the motor got warm it pushed fluid into the resivoir but the seal was bad so it couldn't pull it back when it cooled off......i found out when i kept filling up my overflow.....

LTX

ask your mechanic to pressure test your cap!