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Losing coolant head gasket, liner seal or both?

Fentible

Enthusiast
Messages
35
Location
France
So after standing for several years I've got my little french registered 1984 R4 TL running. The expansion bottle internals were so badly stained it was impossible to see the level of added water (just for flushing and starting purposes). I back flushed the radiator and engine block and discovered that the thermostat had been removed. Once the flushing was completed, new thermostat added, expansion bottle cleaned out and fresh 50 50 coolant added, I ran the engine and took it for a quick trip up the dirt lane outside our house. It ran okay. The level in the expansion bottle dropped and I sorted a couple of leaks at the inlet manifold to cylinder head hose by cutting off the rotted ends, losing about an 1" overall, but which gave me clean ends. Letting it idle for 10 or so minutes, I could detect no leaks from any hose or the radiator. Fast forward 2 weeks and I had time to once again play with the R4 To my horror the expansion bottle was totally empty and even the radiator seemed to only be about half full, I had previously left it topped up to the correct level. No obvious external leaks. I refilled the coolant and took it for a short 2K/M run, after which the expansion bottle level had gone from max to min. No visible external leaks, no steam, from the radiator but the water is going somewhere. The oil level isn't increasing, although there is a tell tale rainbow in water drained from the coolant system. Its losing a fair bit of water but the dipstick doesn't indicate any coolant in the oil, is it likely its just the head gasket or is there the possibility that a liner seal has gone? Its the 845 B1B engine. Thanks George
 
Hi Fentible

After refilling the cooling system, did you bleed the system to remove any airlocks via the bleed nipple protruding from the bulkhead? Renault 4s are susceptible to airlocks and hence overheating.
 
Bleeding is crucial.
Recently done same thing. Flush coolant from engine block. And took me two attempts to bleed sistem totaly. My fan did not kick when it should. Suspect if fan is working. After second bleeding fan run normaly

If there is no obvious leaks in engine bay than it is inside cilinders.
Did you checked heater matrix in cabin?

I would fill up expansion bottle once more. Rebleed sistem and then tried to see if I missed leaking spot.
 
As has been said, try keeping the expansion bottle much higher then the engine while filling it; hanging it from the inside of the bonnet using a wire coat hanger might help. Run the engine at tick-over with the heater and fan fully ON, top up the expansion tank and open the bleed nipples on the pipes near the bulkhead and listen for air rushing out, then watch for liquid running out and then tighten them up. Feel for heat from the heater, indicating that hot water is circulating through the matrix. If the fan's not blowing hot air, there could be an air lock (try massaging the pipes!) or a blockage. If all's well with the heater, let the engine warm up gently and keep topping up the expansion tank, as necessary. There will be loads of air bubbles coming up as the thermostat opens. Feel the pipes to & from the radiator and check they're both hot, which means water is circulating through the radiator. If all this is fine and the air is cleared, all should be well.....
 
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Thanks for the input guys. I never knew what the capped off hose in the engine bay was for...now I do. I never bled the system, I've always found slow filling through the rad cap, with a running engine and occasionally 'burping' the hoses works well.
The heater works, no visible leaks in the cabin bay but I will follow the advised procedure and try again. If no luck its off with the cylinder head. I don't know if its related but when I first start the car and off the choke, the idle is impeccable. Once the engine warms up I can detect a very slight miss every now and again. Timing is on the mark and valve clearances are also spot on. Points, plugs and even ignition leads look to be recent replacements.
 
Getting a new well sealing cap for the expansion bottle made a huuge difference for me (alså 80s TL). It drank the water slowly before, overheated once in a while, and was a pain to bleed (AND had low heat in winter).
Now it just airs itself out while driving because theres so much pressure in the system, heats nicely up, doesn't overheat, and the occasional bleed is much faster.

Oh, but one time it actually was the fat hose below the waterpump that leaked ....

Old bicycle tubes, strips and some tape are a good roadside repair kit, and I've once driven 1400km without any issues with a fix using these.
Just put a fair bit of tube inside the leaking hose, and strip another bit of tubing arond the outside of the hose :D
 
The small miss on idle is pretty common I think. And indeed very noticeable from behind the car. I've had something like that for all 6 years of ownership, and It has never been an issue.
But check if theres any air-leaks between the carburettor and manifold, any air-leaks in the tubes going from the valve cover to the manifold/carb, check if your idle-mixture screw is loose, check if the vacuum tube to the ignition advance is fitted/clean/not broken, check that your petrol filter (if fitted) is clean.
 
Might also just be dirt in the idle-system of the carb.
 
Btw: Have you measured the compression of the cylinders?
 
Sorry Niels, just spotted your last 2 replies. Im about to strip the carb as there is a small leak from the gasket and no I haven't checked compression but will do. I'm also pleased to report that since being advised on the correct bleeding procedure, I don't seem to be losing anymore water.
On a final note I replaced the gearchange bushes. That has to be the most difficult job I have ever done, it took me nearly an hour of sweating and profanity to eventually 'encourage' the plastic bush into the rubber grommet. What a difference to the gearchange though.
 
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