Grey Motor Diagnosis Assistance

[In the Shed]

Hi Folks
Had my Ute our on a run couple weekends ago and did about 350 kms, all went well cruising at 80 -85 km/ hr until nearly home when it kept stopping at the lights and idling a little off. Opened up bonnet and there was a mess from radiator over flow (has no expansion tank). Opened radiator and no fluid to be seen? Temp light never came on and confirmed it works by shorting sensor.

Decided it was time to flush radiator and refill & flush. Topped up radiator and changed oil.

Out in the Ute again and seems ok cruising at 80 - 85 kms/ hr for a run of 400 kms. After a brief stop had trouble starting it and then had no power, was popping and mis firing.

Next day I took it for a run down the road and there is a lack of power but it will run up to 100 km/hr but it’s not happy. Oil looks clean, radiator fluid Level is ok.

Drive line is all standard. There is a sound from engine that reminded me of when manifold was leaking at head. I’m wondering if head gasket has let go? I only have a basic tool kit.

Any tips appreciated as I have 400 kms to get home.

Stephen

[gpi]

Perform leak down test and post results

[ardiesse]

Stephen,

It sounds like your motor has a couple of problems, which may be inter-related.

Simple things first: Ensure your manifold bolts are tight, the carburettor attaching nuts are tight, and the two screws holding the carby's main body to the throttle body are tight.

You might have something as simple as a blocked main jet: Take the air cleaner off, start the motor, rev it up, clap your hand over the air intake for a second, and let the engine clear its throat. If the car now idles, you're sweet.

Funny idle and stalling at lights (cause: lean mixture) can be signs that your manifold gasket has split at one of the inlet ports. If you have WD-40, start the motor and spray around where the inlet manifold bolts to the head. If you can get under the centre leg of the manifold, better, because that's where the manifold gasket often splits. If the idle changes noticeably when you spray WD-40, you have a split gasket. For good measure, also spray WD-40 around the carburettor base.

If this test comes up negative, check your point gap and ignition timing. Overheating and lack of power are symptoms of retarded timing. When the point gap closes up, you get retarded timing as an added bonus.

Still no improvement? Let's move on to compression. You say there's no water in the oil, which is good. Still, it'd be an idea to pull all six spark plugs out and wind the motor over on the starter while looking at the right hand side of the motor. If you see spray or droplets of water come out, that's bad. If OK, put the plugs back in one at a time: no. 1 first, then remove it, then no. 2, then remove it, and so on. With each plug in, turn the motor over by hand and make a mental note of how much resistance the motor puts up in the compression stroke. Take the air cleaner off. If you hear a deep-sounding "fssh" in the guts of the motor during the compression stroke, that's normal leakage past the rings. If you hear a "fssh" out the air intake during the compression stroke, you have a leaking inlet valve. if you (well, your assistant) can hear the exhaust "breathe" during a compression stroke, you have a leaking exhaust valve. If two adjacent cylinders don't put up much of a fight during their compression strokes, you probably have a head gasket leak between the two cylinders. A "choofing" sound like a an exhaust leak is what a really bad head gasket leak sounds like. But in this case you'll have just about no compression at all in the affected cylinders.

Put all the spark plugs back in, top the radiator up brim-full, and start the motor. If the radiator overflows and bubbles come out of the water immediately after you start the engine, that's bad: head gasket leak or cracked head. (A cracked head will also blow water out of the spark plug holes in the test above, so I don't think it's that.)

That's the diagnosis done. Getting the car 400 km home won't be too much trouble. Check the radiator water often, and don't drive too fast. Go gently up hills (you may have no choice in the matter).

Rob

[In the Shed]

Thanks Rob,
Appreciate your help.
I will have a play tomorrow. Driving home “not too fast” is what I do when it was all good! Fortunately the road home is pretty flat

[Errol62]

Even if head gasket is leaking you should be able to nurse her home Stephen. Not ideal obviously but they are tough old donks when it comes to getting a bit hot. Good luck fingers crossed for the drive mate.


FB ute fixer upper, EK van on rotisserie

[In the Shed]

Thanks Clay

[In the Shed]

Report of bush mechanics:

- Manifold nuts tight
- Carb screws tight
- Carb nuts tight
- A/Cleaner off, radiator topped up to the brim then started engine on a fast idle.

Chocked the carby and no bubbles in radiator neck after 2-3 mins. Once motor settled down I squirted WD40 around manifold intakes. No change in idle speed for cylinder intake 1/2 & 5/6, however there was a noticeable increase in revs for intake 3/4.

Checked the points and hmmmmm..... not good. Measured the point gap and I reckon I had 3-4 thou

Put a new set of points in, then proceeded to check the plugs. They all looked reasonable. Did the one plug at a time compression test and no unusual noises just the internal pssst. Cranked the motor over and no observations of z as nothing coming out of plug holes.

Fired it up and it sounds ok but is not happy idling until you spray WD40 around intake of cylinder 3/4 then it is smooth. It is also popping / farting when on the run down from a rev up. Sounds like it’s popping from where manifold meets the head.

So I assume that’s the problem and the fact the mechanic (owner) has been slack in maintaining the old bus !!! Will see how it goes up the road tomorrow.

Stephen

[ardiesse]

You have a split manifold gasket at the centre intake leg.

In what condition are the front tailpipe support and rubber (the one under the rear floor)? If loose or absent, you'll split manifold gaskets on a regular basis.

Also, the inlet and exhaust manifold faces go out of plane, and this is another cause of split manifold gaskets. Take the manifolds off (you'll have to do this anyway) and lay a straightedge along the faces. If there's a noticeable offset between inlet and exhaust faces, it's a good idea to take the manifolds to a machine shop and get the faces milled. This is easier than trying to undo the hot-box bolts . . .

And that reminds me - is your heat riser valve in the exhaust manifold stuck in the "cold" position (where it circulates exhaust around the hot-box)? This also causes orneriness of the type you've described.

While the manifolds are off, squirt lots of WD-40 around the riser valve's shaft, and get two hammers. Tap gently on each end of the shaft until the valve frees up. Nothing will happen for ages, usually, and then it will begin to come free.

Rob

[In the Shed]

Thanks Rob
Entire exhaust was replaced not that long ago. I previously faced the manifold (see my thread “Another EK Ute on SA roads”) but as you say it needs to come off again so I will check with straight edge and feeler gauges.

When manifold was off I wired the manifold heat valve in the open position however will check.

Regards
Stephen

[In the Shed]

Hi Folks
Took it for a spin and still lacked power. Got onto my local Repco store at 11.00 am for a new gasket and they had one in warehouse other side of town. Two hours later it was in store then onto transport co. Next morning at 8.30 it was 450 km from home near me. Jumped on my bike picked up the part and proceeded to swap gasket in the garage see picks. It is now running smooth but still lacks a little power but should get me home, I hope!

Stephen

[Errol62]

Say hello to Jane at the pub for me if you are at Parachilna. Mention the old EK sedan she will know me.

Sent from my SM-G973F using Tapatalk

[yaapeet30]

Hi Stephen,

I recon you have this almost beat with changing the points (did the bush garage have a set of feeler guages?) and inlet manifold gasket. There is definite signs of leakage in more than a couple of spots. Once you get home, the old girl won't know herself after you have checked the timing.

All the best.

[In the Shed]

Hi
When I venture far from home I usually take stuff I never need. This time I had rope, tarp, socket set, spanners and a heap of other odds & ends. Certainly came in handy! Setting the point gap was a guess using the feeler gauges.
S

[FireKraka]

Hi Stephen certainly looks like you have got it licked mate safe trip home, with the gasket leak fixed you may find it will improve after a good run and blow some of the crap out of it..

Clay do we need to ask anymore about Jane at the Pub

Neil

[FbSTDwagon]

I had manifold gasket issues many moons ago on a Grey.

Don’t for get to check the bolt tension when it all warms up, you can normally get another half turn out of the bolts when it is hot.