Hey Guys
I need to pop the head off my motor at some stage to deal with some bad juju ...
- Coffee coloured foam in the cooling system (mainly seen on the radiator cap). Photo attached. There appears to no water in the engine oil .. even after the run down and back to Temora.
- Loosing significant coolant from the radiator overflow. It's not over-heating and runs constantly at around 60-70deg Celsius.
- Some low compression values in a couple of cylinders. Note that I am using a crappy el-cheapo tester here ... so it's the trend I'm looking at.
1. 100. 2. 100. 3. 92. 4. 95. 5. 98. 6. 100
- Noticeable miss at idle, flat spot on take off, starts breaking down at >65mph.
- Tricky to start until at operating temperature.
- Super fumy exhaust (Currently running it lean to see if that helps here. Doesn't seem to)
- Valve stem seals are in desperate need of replacement, whilst the head is off.
I'm hoping the fix is just a new head gasket and have one of Harv's improved versions lined up.
Keen on any thoughts on what beyond the head gasket and valve stem seals is worth doing at the same time ? Obviously will check the valves & seats for any pitting/burning/build up etc. but are there any jobs or simple component updates worth considering ? Not really looking for any performance mods unless its a simple component upgrade.
Please let me know your thoughts.
Steve
Grey Motor Head overhaul
Grey Motor Head overhaul
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- UNADJUSTEDNONRAW_thumb_29a6.jpg (143.59 KiB) Viewed 129 times
EK Special Station Wagon
Serial # EK15997B
585-9931 Twilight Turquoise
EK 1051 Mosaic Turquoise & Athens Grey 225
Serial # EK15997B
585-9931 Twilight Turquoise
EK 1051 Mosaic Turquoise & Athens Grey 225
Re: Grey Motor Head overhaul
Steve,
Executive summary: Don't take the cylinder head off yet. Do all you can to fix the miss at idle and the hard starting first.
- The coffee-coloured foam is rusty sludge. Go to Bunnings and buy a two-kilo bottle of Diggers Rust and Stain Remover (warning: oxalic acid powder. Poisonous, very effective bleach. Don't get it on your clothing). Drain the cooling system with the engine hot. If no water comes out of the drain cock on the LHS of the crankcase, remove the drain cock, and shove some coathanger wire into the hole, working it around until the mud begins to flow, followed by coolant. Put about a cupful of oxalic acid in your cooling system, take the car for a long drive, then drain and refill cooling system. Repeat as often as needed.
- Losing coolant: Sludge in the cooling system makes the radiator cap leak, but slowly. Get the engine up to operating temperature and fill the radiator brim-full with the engine idling, until no more bubbles come out. Then give the engine a good hard rev. If lots of bubbles come out of the water, and it happens every time you rev the engine up, you have either a leaking head gasket (moderately bad) or a cracked cylinder head (catastrophe).
- The (small) variation in your compression pressures is no cause for alarm and suggests that your head's not cracked. I've run grey motors for years with more variation in compressions than yours.
- Find out which cylinder has the miss at idle. Short out each spark plug in turn with a screwdriver. Or unplug and replace the HT leads one at a time if you have boots over the spark plugs. The bad cylinder will be the one with the least noticeable change of engine note on shorting out the spark plug. Does the bad cylinder have lower compression compared with the others?
- The breaking down above 65 mph may be due to over-advanced ignition timing. Start engine and gradually increase engine speed. If the engine starts to stumble and fluff at a couple of thousand rpm, the ignition timing's too advanced. Retard the timing until the engine runs smoothly. Another diagnosis is if the car hunts and surges on light throttle openings at 50-60 km/h in top gear.
- Hard starting is frequently caused by the choke not operating properly. Make certain that your choke closes all the way when you pull the knob out. Straighten kinks in the choke cable and adjust the outer cable in the clamp so that you have the full range of movement in the choke lever.
- Fumy exhaust: Steamy or smoky? Does your exhaust smell of burnt oil? Does the car blow smoke? If you take the oil filler cap off with the engine running, do fumes come out the rocker cover? If yes, yes and yes, you probably need to replace the piston rings. Head's gotta come off for that. And you can flush the cooling system passages out while you're at it.
Check for Leaky Valves: Take the manifolds off. Turn the engine over by hand until number 1 is beginning its compression stroke. Spray a good burst of WD-40 into the exhaust port. Turn the engine over through the compression stroke. Can you hear hissing or bubbling sounds coming out of the exhaust port as you do so? Repeat the procedure for the other five cylinders, taking care to get the WD-40 onto the correct exhaust valve head for cylinders 2,3,4,5. Use the red tube on the pressure-pak. If you hear hissing or bubbling sounds in any of the exhaust ports, that indicates leaky exhaust valves. You may now take the cylinder head off.
- Valve stem oil seals in grey motors do not usually give trouble. The early grey motors don't have them at all. Excessive oil consumption is caused by piston ring troubles first and worn valve guides second.
If you're going to pull the cylinder head off, replace the piston rings while you're at it. And while you've got the pistons out, it's a shame not to replace the bearings. And if you should discover that the camshaft still has a fibre timing gear, well, now's the time to replace it. And things start getting out of hand . . .
Rob
Executive summary: Don't take the cylinder head off yet. Do all you can to fix the miss at idle and the hard starting first.
- The coffee-coloured foam is rusty sludge. Go to Bunnings and buy a two-kilo bottle of Diggers Rust and Stain Remover (warning: oxalic acid powder. Poisonous, very effective bleach. Don't get it on your clothing). Drain the cooling system with the engine hot. If no water comes out of the drain cock on the LHS of the crankcase, remove the drain cock, and shove some coathanger wire into the hole, working it around until the mud begins to flow, followed by coolant. Put about a cupful of oxalic acid in your cooling system, take the car for a long drive, then drain and refill cooling system. Repeat as often as needed.
- Losing coolant: Sludge in the cooling system makes the radiator cap leak, but slowly. Get the engine up to operating temperature and fill the radiator brim-full with the engine idling, until no more bubbles come out. Then give the engine a good hard rev. If lots of bubbles come out of the water, and it happens every time you rev the engine up, you have either a leaking head gasket (moderately bad) or a cracked cylinder head (catastrophe).
- The (small) variation in your compression pressures is no cause for alarm and suggests that your head's not cracked. I've run grey motors for years with more variation in compressions than yours.
- Find out which cylinder has the miss at idle. Short out each spark plug in turn with a screwdriver. Or unplug and replace the HT leads one at a time if you have boots over the spark plugs. The bad cylinder will be the one with the least noticeable change of engine note on shorting out the spark plug. Does the bad cylinder have lower compression compared with the others?
- The breaking down above 65 mph may be due to over-advanced ignition timing. Start engine and gradually increase engine speed. If the engine starts to stumble and fluff at a couple of thousand rpm, the ignition timing's too advanced. Retard the timing until the engine runs smoothly. Another diagnosis is if the car hunts and surges on light throttle openings at 50-60 km/h in top gear.
- Hard starting is frequently caused by the choke not operating properly. Make certain that your choke closes all the way when you pull the knob out. Straighten kinks in the choke cable and adjust the outer cable in the clamp so that you have the full range of movement in the choke lever.
- Fumy exhaust: Steamy or smoky? Does your exhaust smell of burnt oil? Does the car blow smoke? If you take the oil filler cap off with the engine running, do fumes come out the rocker cover? If yes, yes and yes, you probably need to replace the piston rings. Head's gotta come off for that. And you can flush the cooling system passages out while you're at it.
Check for Leaky Valves: Take the manifolds off. Turn the engine over by hand until number 1 is beginning its compression stroke. Spray a good burst of WD-40 into the exhaust port. Turn the engine over through the compression stroke. Can you hear hissing or bubbling sounds coming out of the exhaust port as you do so? Repeat the procedure for the other five cylinders, taking care to get the WD-40 onto the correct exhaust valve head for cylinders 2,3,4,5. Use the red tube on the pressure-pak. If you hear hissing or bubbling sounds in any of the exhaust ports, that indicates leaky exhaust valves. You may now take the cylinder head off.
- Valve stem oil seals in grey motors do not usually give trouble. The early grey motors don't have them at all. Excessive oil consumption is caused by piston ring troubles first and worn valve guides second.
If you're going to pull the cylinder head off, replace the piston rings while you're at it. And while you've got the pistons out, it's a shame not to replace the bearings. And if you should discover that the camshaft still has a fibre timing gear, well, now's the time to replace it. And things start getting out of hand . . .
Rob
Re: Grey Motor Head overhaul
Great summary Rob
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getting my FB ute on the road
EK van on rotisserie
EK van on rotisserie
Re: Grey Motor Head overhaul
Plenty for me to look at there, Rob ... I really appreciate the in depth response and info.
I'll do some diagnostics and report back.
Steve
I'll do some diagnostics and report back.
Steve
EK Special Station Wagon
Serial # EK15997B
585-9931 Twilight Turquoise
EK 1051 Mosaic Turquoise & Athens Grey 225
Serial # EK15997B
585-9931 Twilight Turquoise
EK 1051 Mosaic Turquoise & Athens Grey 225
Re: Grey Motor Head overhaul
The oxalic acid does a good job , I have used it in the past 
I started with nothing and still have most of it left.
Foundation member #61 of FB/EK Holden club of W.A.
Foundation member #61 of FB/EK Holden club of W.A.
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EK DAZ
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- Location: Bay of Plenty, New Zealand.
Re: Grey Motor Head overhaul
Also check the condition of the frost plugs behind the side plate. If these are leaking they will allow coolant into the oil.
EK DAZ