Last year I developed a coolant pressurising issue, which turned out to be the head gaskets. I replaced these and things have been mostly fine. Just a little rough running on LPG at idle. Petrol was fine.

Now I've started to have rough idle on both LPG or petrol. I replaced the ignition leads, as I had no idea how old they were and it didn't help. Today I've connected up the Nanocom and have a lot of misfires just on one cylinder and it appears to only be at idle.
Spark plugs were replaced with the head gaskets.

Now I'm thinking back and I did have issues with the inlet manifold not fitting as well as I wanted when rebuilding and I'm thinking this may be the cause of the misfire.
On top of this, in the past couple of weeks I'm starting to get pressure in the coolant system again :( Although, no coolant loss yet...

Although I was convinced after a lot of checking that the heads didn't need skimming, it looks like they might. However I'm concerned about getting the heads skimmed and the inlet manifold fitting even worse.

Since I've had it, there is a very minor oil leak at the rear of the engine, which I believe is the main seal. I'm seriously considering taking the P38 in for someone else to rebuild it, including removing the engine to replace the main seal and possibly replacing the camshaft etc too whilst it's in. The mileage is unknown as it was a replacement engine a number of years before I bought it.

I'd love to be able to do this myself, but I don't have the space or time at the moment.

Is there anyone in the north west that you'd recommend for an engine rebuild?
If I'm going to do this, I'd like to get it done properly.

If you are having it done, I would suggest top hat liners and do the job properly. It isn't going to be cheap though. I don't know of anywhere in your area, the only places I would recommend are V8Developments (http://www.v8developments.co.uk/ website being updated at the moment but the phone number is there) or Turner Engineering (https://www.turnerengineering.co.uk/, not to be confused with Turner Diagnostics, a completely different company).

I know Turner Engineering would supply the engine, and you could have some confidence that it was done well, but I didn’t think they did any of the garage work?

Thanks Richard.

Yeah the thought process is going towards if I'm going to do this I may as well get it done properly, top hats too.
I plan to keep the P38, so it seems to make sense.

Potentially if I could find the time, I'd take the heads out myself and take them for machining and a refurb, plus drop the sump and swap camshaft etc, but it's the engine out that I don't have the space or equipment for.

I had a look on V8 developments site a couple of weeks ago before it closed and the prices seem fair, although I agree it's not cheap.

ACR (Automotive component manufacturing) is closer to me, they appear to have some good reviews, but seemed more focused on performance rebuilds, seems like they'll be more expensive.
I'll have to call around a few places and get some price estimates.

V8 Dev will remove the engine for you and do the full job from start to finish. No idea how much they would charge for that though and I know Ray isn't keen on working on things with LPG fitted as it just adds to the complication. I took the heads off mine to refurb myself and dropped the short block in with them when I did mine. With the heads already off and an engine crane, taking the engine out is pretty straightforward. Hiring a crane for a weekend would be your other option.

Before you pull the trigger on all this, have you done a compression/leakdown test? and one of those "detect exhaust gases in the coolant" tests?
It might just be a valvetrain issue which you could fix without the engine coming all the way out.

You're probably right, and a full rebuild will fix whatever the issue is, but it might just not be necessary. Also, if your compression numbers ARE all out of whack and you have exhaust in the coolant - you'll feel better about dropping lots of money on a rebuild. Or I would, at any rate :)

I've tested with one of those exhaust gas fluid tests, it did change colour after a while and some revs, but not as quick or as much of a colour change as it did last year.

I need to do a compression test next.

I'm currently going through all the options in my mind.
A rebuild is probably overkill, but it would be nice to know everything has been reconditioned and seals etc replaced.
The quickest solution is probably heads out and re-skim/refurb. Also drop the sump, check the camshaft etc whilst they are at the shop for a refurb. That's very tempting at the moment and just live with the minor oil leak.

I eventually found the time to look further into this today. First I checked for spark on cylinder 3 which was the one I'd been having issues with and all was good. So then I took it out for a short drive with the Nanocom connected and for the first couple of miles it didn't report any misfires. Then once it was up to temperature, they started showing on cylinder 3 at idle.

Back at home, I pulled the fuses for the fuel pump and ignition coils, jammed the throttle open and started testing the compression, these are the results:
Cyl. 8 - 150psi
Cyl. 6 - 135psi
Cyl. 4 - 145psi
Cyl. 2 - 150psi

Cyl. 7 - 150psi
Cyl. 5 - 125psi
Cyl. 3 - 50psi
Cyl. 1 - 150psi

So as expected, cylinder 3 is way out, with cylinder 5 down too.
Cylinder 4 and 6 aren't perfect, but just about within 10%
The compression tester may not be the most accurate, but at least it's highlighted the problem cylinders.

I still have the issue with the lower manifold bolt close to cylinder 3 and 5 in mind, but now also suspecting the stretch bolts may not be up to standard either... Would a poor fit of the lower intake manifold be possible to cause such low compression on it's own?

I'm not a P38 expert but some general advice...

A poor fit on the intake manifold shouldn't effect compression readings.... You ran the compression check at full throttle anyway.

The compression problem could be valve leakage as opposed to ring leakage, have you tried a wet compression test? If only valve leakage were causing the compression problem and if only a HG problem were causing coolant pressurisation you could fix the problem yourself (whip the heads off etc).

The general advice wouldn't leave you with a top-hatted engine though.

True! I'm confusing myself with it now, by overthinking...

Wet compression test is next to try, it got dark before I got chance earlier!

I'm hoping it is the valves, if so I'm thinking of purchasing refurbished heads and a set of ARP head studs, that way I can ensure a better install, rather than using stretch bolts again.

I would of course look at the crankshaft etc too this time and check the engine condition a bit more thoroughly.

Yeah top hat liners would be nice but then it takes me back away from something I can do myself on the driveway.

Will see what the results of a wet compression test reveal.

A wet compression test can be inconclusive on a Vee. Ordinarily the oil will seal the rings so if the compression goes up, it's ring, if it doesn't, it's valves. But with a Vee engine the oil will sit at the bottom of the bore so not seal the rings anything like as much. If you put a lot of oil in then the compression will go up anyway as the oil will partially fill the combustion chamber and reduce the chamber volume. I'd say your suspicion of a problem with the stretch bolts is the most likely and the gasket is starting to leak around where one of the bolts is. You'll soon know as it will come undone far easier than the others.

Gilbertd wrote:

A wet compression test can be inconclusive on a Vee. Ordinarily the oil will seal the rings so if the compression goes up, it's ring, if it doesn't, it's valves. But with a Vee engine the oil will sit at the bottom of the bore so not seal the rings anything like as much. If you put a lot of oil in then the compression will go up anyway as the oil will partially fill the combustion chamber and reduce the chamber volume. I'd say your suspicion of a problem with the stretch bolts is the most likely and the gasket is starting to leak around where one of the bolts is. You'll soon know as it will come undone far easier than the others.

Agreed. Though with a RangeRover you could park it on a banking so the whole vehicle is leaning to one side thus making the cylinder bank to be tested more vertical lol.

or you can use the little hose that comes with the wd40 tin,( i have one about 150mm long) and spray it up to the top of the piston , hold on to the little hose or it will fly off in the cylinder, just another option.

I would say its head gasket as its low on 1 bank & leak between 3-5 probably water corrosion --- pink antifreeze can destroy h/gastets ---- had that happen on several Toyota 6 liter 6cyl ---- can't see it being valve's related as usually it's 7/8 has valve issues
As inlet coming off --- check cam lobes --- rods

Just looking to order a few things to get started on this when I have a free weekend.
The ARP stud kit appears to be part no. 157-4301, however it seems the only place in the UK with stock in Rimmer Bros and they don't mention a part number... https://rimmerbros.com/Item--i-RB7728--SelectedCurrency-1?gclid=EAIaIQobChMIo675kZnV9gIVR7DtCh3D9gWcEAQYFCABEgJf2PD_BwE - This seems to be the same kit though, anyone ordered this kit before from them?

As for the heads, I have decided the best option is to go for a set of reconditioned ones on an exchange basis, that way it minimises time needed to get this done and I get a set of cleaned heads, skimmed and tested and no need to worry about valve seals etc. Has anyone used ACR Deeside before? Not the cheapest, but seem to have good reviews and are relatively local to me. Any other recommendations for a decent set of reconditioned heads?

Now a dumb question:
Is there anything else I should be aware of using studs instead of stretch bolts? I guess clearance to get the heads on is still ok, without removing the engine?

www.realsteel.co.uk/section1.pdf, page 5 right hand side.

For reconditioned heads, give V8 Developments a call (http://www.v8developments.co.uk/index.shtml), their website is being worked on but the phone number is there.

If you screw the studs into the block then try to fit the heads over them, they probably won't go on as other stuff will get in the way. You put the head onto the block, screw the studs in like you would if they were a bolt, nip them up using the hex hole in the end (they do just need nipping up, they don't need to be tight but make sure you have cleaned any oil or coolant out of the holes so they screw in fully) then lube the washers and fit them and the nuts. Tighten in the correct sequence, to 30, then 50 then 65ft/lbs.

Rob done a good job at V8 Developments still going strong cost my £4200 with some extras.

So after a bit of delay, busy with other things, I've made some progress on this.

ARP studs and all the gaskets etc were ordered and then I've just been waiting for a set of recon heads to arrive from V8 developments, which arrived this week! Today I've stripped the engine down and the heads off. The head bolts were actually all very similar in feeling when cracking them loose and the head gaskets looked in very good condition, so maybe I did a better job than I originally thought... And maybe the head bolts weren't too bad either.

However upon removing a couple of tappets, they are pretty worn, some are mostly flat, but others are well dished. Especially the ones around the main 2 problem cylinders. The camshaft is showing signs of wear too.

So time for a new camshaft and tappets. I'm guessing removing the radiator and fans is enough to take the camshaft out?
Anyone recommend a camshaft and tappets other than the genuine ones?
I think I might replace the radiator too, as it's starting to crumble a bit around the end where the top hose pushes on.
At which point the thermostat may as well be replaced too! Already replaced the water pump last year.

The cylinders themselves looked okay to me, I can't see or feel any ridges around the liners. None looked steam cleaned this time (last time the front 2 cylinders had been cleaned by the leaking head gasket). Hopefully these are okay and the rings are fine.

So camshaft, tappets, timing chain, radiator, thermostat, drop sump and replace the gasket, new front cover gasket, plus all the other gaskets from the heads up as originally planned. Anything else I should look at replacing?

It's all a bit of a daunting task really. How do I get the bolt of the crankshaft pulley off - is there some sort of tool to stop the pulley and engine just turning?

I've not been that far into the engine as your looking at, but we did have the front pulley off mine (I think in the process of fixing an oil leak if I remember correctly). When it was done my mate made up a tool to hold that pulley so we could undo the bolt. You might get it to come off with an impact wrench if it doesn't matter that the engine turns a bit otherwise, I've done that on a few pulleys though usually when they are on the aux belt where timing isn't an issue.

I will take a photo of what he made, that worked ok, though we did have another spare pulley to make the tool up with which helped!

LRT-12-080 is the tool to stop the engine turning whilst leaning on the crankshaft pulley bolt.

Basically a hub that bolts to the pulley with a lever to wedge against something solid to stop things turning. Easily made if you have access to a guy with a lathe et al.

Once you find the dimensions. I have drawings for the one I made which is a bit different from the usual run because the hub and lever are separate pieces.

Much easier to fit. My lever is far longer than the usual versions so it sticks up past the right hand side of the engine. My crank bolt came undone easily with a long impact type socket on the nut turned by a big Britool 3/4 drive torque wrench sitting straight(ish) up past the front of the engine so I could opeate the torque wrench and holder handle together. Plenty of feel that way and all done standing comfortably in front of the car. Two 3 ft (ish) handles used together are effectively a 6 ft breaker bar so I was unsurprised that it came out fairly easily. Plan B was to wedge the tool handle on the ground with both hands on the bar.

You need a long socket to pass through the tool. Impact types are hex form and, if an OK breed, slightly modified to spread the load off the corners. I bought a Nielson / US Pro branded one as being good enough for this one job I needed it for and not professional expensive.

PM me if you'd like the drawings.

Various shade tree options of wedging the pulley or flywheel. Some involving shocking the bolt loose with the starter motor. Not a fan of such options as the consequences of failure can stretch from naughty words and waiting for the bruises to heal right up to major engine damage. The last being somewhat conta-indicated when engaged in repairing the beast.

Clive