Fouling Plugs

disco2hse · Post by **disco2hse** » Sun Feb 22, 2009 8:30 am

A real rarity.

Wish they could have incorporated some of those features into the series models ::wistfully::

How about posting some pic's we can have a drool too.

Oh and inside and out too please :p

vanquishspirit · Post by **vanquishspirit** » Sun Feb 22, 2009 8:47 am

I will if someone would like to tell me how!!!!!!!!

djam1 · Post by **djam1** » Sun Feb 22, 2009 9:23 am

vanquishspirit wrote:thanks Disco2 HSE. So what will cause the bores to glaze then? Is it modern fuels that leave a residue which then hardens off and renders the piston rings unable to do the job they are meant to? Anyway, I checked my compressions which are all about 120 to 140 pounds. Bear in mind this is the very early RR with a 10.5:1 compression ratio. I am assuming that becasue the comps are all good then I dont have glazing. Time will tell. thx Andrew

Vanquishspirit
To my knowledge a 1972 Range Rover had 8.5:1 engines not 10.5:1
also 120-140 pounds on a 10.5:1 engine isnt a good thing.
If it is a 10.5:1 could you share the engine number with us I am intrigued.
I will also state that with over 30 years of Rover ownership I found my 1972-73 Range Rover the best vehicle I ever owned.
With the description you give it sounds like it has never done any real work take it for a drive and give it some real work
(I know I live in Australia but 100 miles isnt even a drive) give it some curry I have never know a Rover V8 with under 400 thousand Ks on it that burnt oil.
Let it tow something heavy and let it work if it sounds good and burns a little oil do this and save yourself some expense you wont be dissapointed

disco2hse · Post by **disco2hse** » Sun Feb 22, 2009 9:43 am

vanquishspirit wrote:I will if someone would like to tell me how!!!!!!!!

lol

Easiest thing to do is:
1 Post your images online somewhere like Photobucket then copy the static link url to the image.
2 In your posting click on the "Img" button, paste the url you copied, then click on the "Img" button again.

That should just about do it.

Couple of things. If you have a bunch of images have two browser tabs or windows open and flick between them, copying, clicking, pasting, clicking again,... until you are finished. Tidy up and add text text after.

Make sense?

stirlsilver · Post by **stirlsilver** » Sun Feb 22, 2009 12:42 pm

What's that? Glazed pistons... I know what that is all about... Mine are glazed after 5 years!

Yep... when I fixed the blown head gasket the cylinders were like mirrors!! I didn't do anything about it though. It really needs to be honed out and a new set of rings put in. On 15W-20 oil it was consuming a reasonable amount of oil (as can be seen from the carbon buildup on the cylinders) 40W-70 oil fixed it though. Yes I know it is thick oil, but it actually works quite well in the engine.

disco2hse · Post by **disco2hse** » Sun Feb 22, 2009 8:00 pm

All you need with them is some Windolene

Make 'em reeaally shiny.

But that is the point I was making. Just because the cylinders are glazed doesn't necessarily mean you have to take it all apart and rebuild the engine, again. I am sure there are a gazillion engines out there with glazed bores because their owners have left them idling too long, say in stationary traffic (which is why I never leave my engines idling for any length of time, especially the TD5 which is apparently prone to it).

djam1 · Post by **djam1** » Sun Feb 22, 2009 8:48 pm

Stirling
Did you run it in on LPG ??
This can happen if you do, they should be run in on petrol then run on LPG

stirlsilver · Post by **stirlsilver** » Sun Feb 22, 2009 10:05 pm

djam1 wrote:Stirling
Did you run it in on LPG ??
This can happen if you do, they should be run in on petrol then run on LPG

It did about 200km on petrol before being converted over to LPG. You are correct on running engines in on petrol. However when I built the engine with 12:1 CR, and then ran it on petrol, I found it wasn't very happy on 98 octane fuel + octane booster. It would detonate under medium load. When it got changed over to LPG it all went away and ran very well. But yeah the consequence of that is the glazed bores.

It would be an easy fix (cylinder heads off, sump off, pistons out and a hone with some new rings) but it runs quite well. I've compared this engine with a low comp 3.5L one in a range rover and mine has SOO much more torque down low. It seems to run out of puff beyond 4,000 rpm but I think that it is a fueling problem.

Anyway, not to get too side tracked, I would agree that this is what has happened with vanquish's engine in regards to the oil consumption. Obviously glazed cylinders can be caused by incorrectly running an engine in, but i've also been told that it can happen if you use rings that are made of certain materials.

vanquishspirit · Post by **vanquishspirit** » Sat Feb 28, 2009 5:58 pm

ight guys, I am trying to organise some photo uploads today. Howeve, I have now taken the heads off and its pretty horrible in there. Lots of carbon build up and really black and oily. I can see that the valve stems are very dirty too with carbon build up, plus the big dread. I think fromwhat I have been told the bores lok too shiny. Blast.I really did not want to have to taken the pistons out. I am now minded to just whip out the rest of the engine and have it rebored and maybe run in on a dyno. I think what hppened is the guy who put the engine in for me filled it with a syynthetic oil and probably let it idle over for too log whilst he set up carbs and ignition etc. Shoot. Anyway will try to post a photo of the bores tommorrow as well. Thanks for the help.

vanquishspirit · Post by **vanquishspirit** » Sat Feb 28, 2009 6:18 pm

one more thing, you are quite correct it is a 8.5:1 engine ot a 10.5:1. The book says it shoudl have a compression of 155 lb.sq in. What do you think is acceptable for the engine, given the fact that it has had new rings, valves etc?

vanquishspirit · Post by **vanquishspirit** » Sat Feb 28, 2009 7:06 pm

try this , I hope it works.

http://s714.photobucket.com/albums/ww14 ... ishspirit/

map1275 · Post by **map1275** » Sat Feb 28, 2009 9:52 pm

Was thin in one of the glossy magazines recently?

Anyway back to the story...

Heads are off so measure piston to bore clearance. This determines what the repair will be.

There is nothing wrong with doing a ring and bearing rebuild. It's just that too many people use it as an excuse for penny pinching, instead of seeing whether the motor is within specs to accept this. If its within tolerances then grab a hone.

I would expect you to have some trouble finding an engine dyno.

vanquishspirit · Post by **vanquishspirit** » Sat Feb 28, 2009 10:39 pm

it was in a magazine fairly recently you are correct. It has had a full bearing rebuild 2500 miles ago, so really its just the valve guides and the possible bore galzing that bothering me. Whats the best way to measure the bore with the pistons in? Maybe a simple feeler gauge placed between the piston and the bore?

Also, I am told there is a way of fitting oil seals to riginal guides that never had them, any ideas?

What about deglazing by putting some Vim down the inlet manfold whilst its running!!

map1275 · Post by **map1275** » Sun Mar 01, 2009 8:28 am

I've always heard of the Ajax method but never been game to try. Surprising I haven't done this to some one else's car by now though.

I would stuff it down the plug holes and spin the engine over. Otherwise it will just combust. If you are intent on pulling the heads, then a teaspoon full in each cylinder couldn't really hurt.

If you are fitting the original design of stem seal then there is no need to even remove the head. However I believe you decided the guides were the issue? In which case any stem seal will only be a temporary repair.

The later design of stem seal is like later (most) Minis. This is an umbrella and requires a groove machined into the guide. No reason why you couldn't modify normal guides but there is no way of doing this on car.

Your head has replaceable guides. Though there are a couple of methods of reclaiming the old guides. Basically they are sleeved. Some reconditioners favour this method.

Feeler gauges as per the shop manual is still the simplest way. Otherwise its micrometers.

vanquishspirit · Post by **vanquishspirit** » Sun Mar 01, 2009 11:12 am

sorry, I did not make it clear. The heads are now off and the bores do look a little shiny, although I cannot recall what they shoudl look like if they are not glazed. I will take the valves out and check the tolerance but will probably have a set of later guides pressed in. Not keen to put Vim or Ajax into the engine really, just thought I would see what you guys said about it. I am also thinking of fitting a later set of heads I have with bigger valves. Not sure whether this will work ok with the 8.5:1 engine and the existing carburation though.