Who else can't get a simple motor to run properly ?

Hi Shane.

So how does that petrol get into the combustion chamber??

the injectors seem the only path into the cylinders or a cold start injector, if one is fitted.
 
That is the fuel pressure regulator pouring full pump pressure straight out of the vacuum capsule on the top of it (so it floods straight into the inlet manifold where the vacuum pipe plugs on ). this plugs in right beside No 8 cylinder!
 
So you hydrolocked your engine on cylinder #8 (at least) with petrol because the diaphragm in the fuel pressure reguator capsule is cactus, right? I bet there's a lot of petrol in the oil too.

Measuring the height of the piston at TDC is still possible even with plug holes on an angle. You only need relative measurements here, not absolute. For an accurate result you need to somehow make sure the dial gauge (or measuring implement - it can even be a stick) is perfectly lined up with the plug hole (to take the plug hole relative position to the piston top as a reference) and can't move sideways. Measure two cylinders and compare. An adaptor might be needed, but I am sure you have the imagination to come up with a makeshift one or if you have a lathe can make a very reliable one.

Or maybe it's worth trying to take some measurement no matter how dodgy any way you can first to see if there's a huge difference and then decide if it's worth going to more trouble for a more accurate result.

This is just because it's the easiest thing to do before you go to the length of doing Col's method and also does away with all the other variables of a leakdown test (carbon on valves, stuck valves, broken rings, etc). Or taking heads off, etc.
 
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Yeah, I have the motor there out of the parts car. I"m going to run the compression tester over it ... it its ok, I'll plug that in for now. At least I know this motor probably only needs repair to one cylinder (so long as it didn't crack the liner). A rod or broken rings should be a simple fix. I'll pull it out rather than mess around with it in the car. Certainly I'll pull the head so anyone that is interested can see what the damage is.
 
So you hydrolocked your engine on cylinder #8 (at least) with petrol because the diaphragm in the fuel pressure reguator capsule is cactus, right? I bet there's a lot of petrol in the oil too.

Measuring the height of the piston at TDC is still possible even with plug holes on an angle. You only need relative measurements here, not absolute. For an accurate result you need to somehow make sure the dial gauge (or measuring implement - it can even be a stick) is perfectly lined up with the plug hole (to take the plug hole relative position to the piston top as a reference) and can't move sideways. Measure two cylinders and compare. An adaptor might be needed, but I am sure you have the imagination to come up with a makeshift one or if you have a lathe can make a very reliable one.

Or maybe it's worth trying to take some measurement no matter how dodgy any way you can first to see if there's a huge difference and then decide if it's worth going to more trouble for a more accurate result.

This is just because it's the easiest thing to do before you go to the length of doing Col's method and also does away with all the other variables of a leakdown test (carbon on valves, stuck valves, broken rings, etc). Or taking heads off, etc.
Hi Shane, I agree with schlitzaugen.

You will need to replace the vacuum fuel pressure regulator anyway, whichever engine you decide to use - yes? So I still suggest that before you make this into an even bigger job, resolve vacuum fuel pressure regulator (swap/replace), and see if you can drive the vehicle for a couple of days, even a decent hour drive would be OK. Check if there is still a missfire, Then do the compression check again. Then depending on the outcome of the compression check, do the "rough" piston height measurement to confirm if the conrod has even bent - it may not be bent at all.

This way there are fewer hours expended and you may not need to swap the engine.

PS: A bit of petrol in the oil is not a big concern, a run with the engine up at operating temperature will vaporise most of it.

PPS: The petrol getting into the No: 8 cylinder also explains the wet sparkplug.
 
Hi Guys,

I've had the fuel pump unplugged since the day it wouldn't start (I was using the LPG system only to narrow down the problems .... as that rules out all of the injectors and ECU's etc...). Its running on 7cylinders on gas :( ....

Its just a standard fuel pressure regulator. It seems no-one has heard of one dying in the fashion before. Lucky me :clown:

s-l500.jpg


this is a citroen CX one .... all fuel injected cars have them :) Its just a standard gas system (ie: not injected gas) so that rules out the fueling system as an issue with the poor running/7cylinders
 
Hmmm. Not sure. I mean if the plug is fouled so badly from starting it on petrol it may not spark at all.

Like I said before, just a rough check of piston depth at TDC is easy peasy though I understand it doesn't help much (I mean you could have all the problems mentioned above even if the conrod is not bent). Thing is, the only problem that would mean the engine has to come out is the bent conrod. All else can be managed without taking the engine out. If the conrod checks out fine, even a bent valve can be checked from above taking the rocker cover off I imagine. Yeah, this is a bit more involved, but I imagine doable (I don't know anything about that engine though). Anyhoo doesn't sound as involved as taking the engine out and stripping it to find there was nothing wrong with it.

That said, I am now wondering why did the second breaker plate (ignition doodad) get flogged so quickly? Is it possible the camshaft that drives the dizzy (or whatever arrangement you have) is verschnickered? How did it fail? Mechanically? Electrically?
 
Before pulling engine apart check push rods / valves are functioning. The Indian rope trick is required here
Rope trick Can dismantle springs and collets, rockers, seals and push rods and check nothing is bent
Pistons/rings fail before connecting rod especially at cranking speeds
As a previous Rangie owner, they actually all do this, alphabetically or numerically to drive you wild.
Look on the bright side of life, you still have 3 spare cylinders.
They added 4 cylinders to the original 1948 motor to get you home.
Happy New Landrover Year
 
Before pulling engine apart check push rods / valves are functioning. The Indian rope trick is required here
Rope trick Can dismantle springs and collets, rockers, seals and push rods and check nothing is bent
Pistons/rings fail before connecting rod especially at cranking speeds
As a previous Rangie owner, they actually all do this, alphabetically or numerically to drive you wild.
Look on the bright side of life, you still have 3 spare cylinders.
They added 4 cylinders to the original 1948 motor to get you home.
Happy New Landrover Year

I ran it with the drivers side rocker cover off... the valves all seem to be doing valve type things :) .... They certainly aren't bent. When you think about it. The valves are both closed on the compression stroke, so they shouldn't be affected :unsure:
 
Would it be correct to say that you would not really be able to tell if they were completely closed unless you checked that you have the correct valve clearance ? I wouldn't expect the valve / s to be bent hugely. Only a tiny bit will cause a bad seal. But if so, it'd be the inlet....it's softer than the exhaust.
 
Would it be correct to say that you would not really be able to tell if they were completely closed unless you checked that you have the correct valve clearance ? I wouldn't expect the valve / s to be bent hugely. Only a tiny bit will cause a bad seal. But if so, it'd be the inlet....it's softer than the exhaust.
I'll pull the head and see once the motor is out :)
 
Even if a valve was bent (or even a conrod) the car wouldn't necessarily run on less cylinders unless they were catastrophically bent. There's some other problem elsewhere and I think it is not all to do with the fuel pressure regulator problem. I would try to fix this problem and the pressure regulator before looking into the bent valve/conrod issues.
 
I'm really good at this stuff. I figured I'd whip the head off and find out what actually happened... Yeah, that is supposed to be an alloy engine block right? I've ended up twisting the edges off the firewall head bolt, so I'll have to go retrieve my engine crane and pull the motor out (and hopefully get that head bolt out). The two front head bolts ..... My breakers bar would be nearly 1meter long. I was bending it so far that it was almost impossible to hold the socket in positiion as the lever would hit something. How on earth are those bolts easily 500Nm ++ and there still be thread in the alloy block.

Oh, and the pushrod assembly has munched the threads on the bolt above No 8 cylinder (unrelated to me issues though this would be).

I just googled it... those head bolts should be 95Nm .... that is something I could undo with a standard ratchet..... Not fail with a 1meter breakers bar and impact socket!

The problem I'll have is once the engine is out. These head bolts are so tight, I'll be just turning the motor on the ground rather than loosening the bolts. This could be fun!
 
I'm really good at this stuff. I figured I'd whip the head off and find out what actually happened... Yeah, that is supposed to be an alloy engine block right? I've ended up twisting the edges off the firewall head bolt, so I'll have to go retrieve my engine crane and pull the motor out (and hopefully get that head bolt out). The two front head bolts ..... My breakers bar would be nearly 1meter long. I was bending it so far that it was almost impossible to hold the socket in positiion as the lever would hit something. How on earth are those bolts easily 500Nm ++ and there still be thread in the alloy block.

Oh, and the pushrod assembly has munched the threads on the bolt above No 8 cylinder (unrelated to me issues though this would be).

I just googled it... those head bolts should be 95Nm .... that is something I could undo with a standard ratchet..... Not fail with a 1meter breakers bar and impact socket!

The problem I'll have is once the engine is out. These head bolts are so tight, I'll be just turning the motor on the ground rather than loosening the bolts. This could be fun!
You need to use six sided sockets and not your standard 12 point sockets when undoing bolts like this. I have had something like this happen to me and managed to get the bolt out using six sided sockets such as impact sockets.
 
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You need to use six sided sockets and not your standard 12 point sockets when undoing bolts like this. I have had this like this happen to me and managed to get the bolt out using six sided sockets such as impact sockets.
yeah that's what I'm using. I might need to chase up an impact 1/4 whitworth so its a bit tighter on the bolt. I can't get onto the bolt and hold the base of the breakers bar to stop it twisting off with the motor still in the car.
 
Does a rattle gun work in this situation? Obviously would need to be a bit more hairy chested than the little Ozito ones we have...
 
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Chemsearch Yield will wick into the threads reducing your 500Nm torque.
Expensive but we used all the time in Industry
 
Does a rattle gun work in this situation? Obviously would need to be a bit more hairy chested than the little Ozito ones we have...
I've got a 3/4" rattle gun that I can use once the motor is out. My father just turned up with my engine crane. We got the big jack handle and extended the breaker bar out to 2meters .... but just started twisting the socket off the head of the bolt again (even with me holding it against the bolt head and him pulling on the bar). The problem is you can't get an exactly straight pull at it while its still in the car. The head wasn't going to fall off that is for sure!!
 
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