Why My Car Has Been A V7 All Along.

Junkman

Junkman

Member
This weekend I found out why my car has been running on 7 cylinders for a while. The pushrod of the exhaust valve of the no.1 cylinder was missing! I therefore removed the inlet manifold and there it was, peacefully lying in the lifter valley, severely bent and snapped in two. Pics to follow.
 
Right.

I have never seen so much tar in an engine. Everything was gunked and sludged up. There was zero oil coming to the rocker shafts, the cylinder head tops were essentially dry at all times. I removed both rocker shafts, took everything apart, cleaned it out, checked whether oil is coming from the holes in the bosses the rocker shaft holders are bolted to, which it didn't. So I had a good poke around with welding rod and removed yet more sludge out of them.
Now everything is clean and the engine is properly oiling. Nothing is stuck, the valves get actuated properly, and open and close.

Why that one pushrod bent and snapped remains a mystery.
 
Junkman wrote,...
have never seen so much tar in an engine. Everything was gunked and sludged up. There was zero oil coming to the rocker shafts, the cylinder head tops were essentially dry at all times. I removed both rocker shafts, took everything apart, cleaned it out, checked whether oil is coming from the holes in the bosses the rocker shaft holders are bolted to, which it didn't. So I had a good poke around with welding rod and removed yet more sludge out of them.
Now everything is clean and the engine is properly oiling
Click to expand...

Hello Junkman,

From what I have seen, the quantity of sludge within the RV8 engine is largely dependent upon the type of oil used, but more importantly the frequency of the oil changes. Regular oil and filter changes every 3000 miles or less is important as is the time interval between the changes. If a car only sees 1000 miles or less per year, then the oil should still be changed every 6 to 12 months maximum. Not doing so will initiate sludge formation.

Tin gaskets and 14 bolt heads can especially when regular oil changes are not followed lead to combustion gases leaking into the lifter gallery resulting is sludge formation. Again regular oil changes will prevent this from happening.

How often has the oil in your engine been changed? What type of oil has been used?

Ron.
 
SydneyRoverP6B said:
Hello Junkman,

From what I have seen, the quantity of sludge within the RV8 engine is largely dependent upon the type of oil used, but more importantly the frequency of the oil changes. Regular oil and filter changes every 3000 miles or less is important as is the time interval between the changes. If a car only sees 1000 miles or less per year, then the oil should still be changed every 6 to 12 months maximum. Not doing so will initiate sludge formation.

Tin gaskets and 14 bolt heads can especially when regular oil changes are not followed lead to combustion gases leaking into the lifter gallery resulting is sludge formation. Again regular oil changes will prevent this from happening.

How often has the oil in your engine been changed? What type of oil has been used?

Ron.
Click to expand...

It hasn't been changed for 16 years and the car did about 1000 less than 1000 miles a year during this period. I have no idea what oil was selected for this operational state, but it is tar now. Since I reanimated the car, I changed the oil altogether nine times within less than 800 miles. It didn't improve things much and when one cylinder stopped working altogether I figured it's time to take the top end apart and check things over, which is herewith done.
It could be all back together again already, but I decided that this is a good opportunity to paint my rocker covers, inlet, air ducts and filter box, and rebuild my carburetters and dizzy. It'll all be back together on Sunday.

Everytime I do open heart surgery on any old engine, I fill it with Morrisons 20-50 for 7.99 a gallon and let it run until it's hot. Then I dump it, fill it with the correct oil and change the filter.
 
SydneyRoverP6B said:
Junkman wrote,...
have never seen so much tar in an engine. Everything was gunked and sludged up. There was zero oil coming to the rocker shafts, the cylinder head tops were essentially dry at all times. I removed both rocker shafts, took everything apart, cleaned it out, checked whether oil is coming from the holes in the bosses the rocker shaft holders are bolted to, which it didn't. So I had a good poke around with welding rod and removed yet more sludge out of them.
Now everything is clean and the engine is properly oiling
Click to expand...

Regular oil and filter changes every 3000 miles or less is important as is the time interval between the changes. If a car only sees 1000 miles or less per year, then the oil should still be changed every 6 to 12 months maximum. Not doing so will initiate sludge formation.

Tin gaskets and 14 bolt heads can especially when regular oil changes are not followed lead to combustion gases leaking into the lifter gallery resulting is sludge formation. Again regular oil changes will prevent this from happening.

How often has the oil in your engine been changed? What type of oil has been used?

Ron.
Click to expand...

Oh I must be a sinner then, I changed the oil about 6 months ago the first time since 1993 or 4 prior to that it was regularly changed once every year or 6000 miles however about 6 months after I took ownership of it in 1988 I flushed the engine and put some Teflon based oil treatment in the engine and since that time the engine oil never got dirty or sludgy, at an oil and filter change the oil that came out was pretty much the same colour as when it went in (Visco 2000 or 3000) the engine now has 235,000 KMs on the clock and has never been apart or strippedand has only ever had a cam and rockershaft change back in 1989/90. The engine neither smokes or uses oil has excellent compressions or piston slap.
Other than the PTFE/teflon treatment all those many years ago I can see no reason why this is so and I can not disbeleive the overwhelming evidence that says that this should not be so having heard so many stories and seen the photos of the engine internals of sludged up engines.
Although I dont place much faith and am pretty sceptical about any form of engine treatment I would suggest that a once only treatment of the product that I used may be benificial and help reduce wear plus keep your oil in nice clean sparkly condition.

Graeme
 
ghce wrote,...
Oh I must be a sinner then, I changed the oil about 6 months ago the first time since 1993 or 4 prior to that it was regularly changed once every year or 6000 miles however about 6 months after I took ownership of it in 1988 I flushed the engine and put some Teflon based oil treatment in the engine and since that time the engine oil never got dirty or sludgy, at an oil and filter change the oil that came out was pretty much the same colour as when it went in (Visco 2000 or 3000) the engine now has 235,000 KMs on the clock and has never been apart or strippedand has only ever had a cam and rockershaft change back in 1989/90. The engine neither smokes or uses oil has excellent compressions or piston slap.
Other than the PTFE/teflon treatment all those many years ago I can see no reason why this is so and I can not disbeleive the overwhelming evidence that says that this should not be so having heard so many stories and seen the photos of the engine internals of sludged up engines.
Although I dont place much faith and am pretty sceptical about any form of engine treatment I would suggest that a once only treatment of the product that I used may be benificial and help reduce wear plus keep your oil in nice clean sparkly condition.
Click to expand...

Hello Graeme,

I too have used a teflon PTFE treatment in my original engine which saw over 203,000 miles (327,000km) upon retirement in 2007. I would add a can to the engine every 50,000 miles (80,000km) and did so over approx a 20 year period. I would also change my oil every 2000 to 2500 miles. I have subsequently read that such treatments are not recommended, and that the oil galleries can indeed become blocked through its use. I will not use it in my 4.6 that now powers my Rover.

Allowing the oil to remain within the engine for 17 years is a very courageous move and not one that I would choose to do. Only time will tell if you have compromised the longevity of your engine.

Ron.
 
To be fair the Rover did not get a lot of use over that period and was fresh oil from the beginning of that period and when changed it came out looking as fresh as it had gone in but i must admit I felt very guilty leaving it that long and it felt like a great weight was lifted once i had changed it :LOL: .
The product I used was Nulon which I presume was the same as you used? I only treated it once as I had some concerns as to over use have seen some reports regarding build up of degraded PTFE/Teflon, now the car is back in daily use it will get the recommended 6 month changes, though now the worry will be the lack of ZDDP in modern oils though I have seen a ZDDP additive being sold and may investigate that as a means of reducing wear.
As an aside have you seen much literature on the use of moly as an additive to motor oils?

Any way back to the origional topic, we used to own a 1957 Hudson Hornet equiped with a 327 V8 with hydraulic lifters, it was at one point a common occurance to have the push rods bent and on occasion displaced from there normal operating positions and the manifold and heads came off a few times till we discovered the cure was out of spec lifters leaking down to easily, once changed and the push rods straightened and or replaced for the 3rd time there were no more problems.

Graeme
 
ghce wrote,...
The product I used was Nulon which I presume was the same as you used? I only treated it once as I had some concerns as to over use have seen some reports regarding build up of degraded PTFE/Teflon, now the car is back in daily use it will get the recommended 6 month changes, though now the worry will be the lack of ZDDP in modern oils though I have seen a ZDDP additive being sold and may investigate that as a means of reducing wear.
As an aside have you seen much literature on the use of moly as an additive to motor oils?
Click to expand...

Hello Graeme,

Yes indeed, it was Nulon. I used two types,...one which would last just one oil change, and the premium gold edition which would last for the 80,000km regardless of how many oil changes ensued over that distance.
I did record in my notes that the engine's fuel economy showed an improvement once I started using the Nulon. I also recall reading a road test in a motoring magazine at the time (around 1987) where a Holden Commodore had a fill of engine oil and a can of Nulon. The engine was then emptied of all the oil, and the engine started. The oil light came on and the car was then driven at road speed from Melbourne to Sydney over a distance of approx 1000km. The engine was then dismantled and all parts examined. No measurable wear was detected, the PTFE protecting the engine components so it was said. It was largely this article that encouraged me to start using it. I might even buy another bottle and keep it in the boot just in case... :wink:

On the subject of ZDDP, Penrite HPR 30 as it is sold in Australia contains ample ZDDP, and was the oil recommended by Land Rover for my engine.

Molydbenum Disulfide...http://www.metcoat.com/molybdenum.htm

A product like this was applied to my new camshaft and lifters etc prior to the engine being started for the first time.

Ron.
 
yep the long life Nulon, I think at the time they called it Nulon 30, I still have the brochure on it some where from the origional treatment. I remember the quoted case of the Holden, I suspect it did it's 1000 miles on the back of a car transporter :LOL: but it certainly seems to have kept the engine oil clean, I had expected to have pulled the engine down a long time ago and done piston, rings and bearing but I am not complaining at the longevity of the engine and its almost Japanese like durability.

Moly works best as a friction reducer on ferris metals only so probably wont help white metal bearing or aluminium piston to bore wear but would help in the lifter and rocker regions of the motor not to mention the oil pump, unfortunantly here in NZ it's as scarce and hard to get as an honest politician and the only way I can get it in a pure paste form is from the USA.


Graeme
 
ghce said:
yep the long life Nulon, I think at the time they called it Nulon 30, I still have the brochure on it some where from the origional treatment. I remember the quoted case of the Holden, I suspect it did it's 1000 miles on the back of a car transporter :LOL: but it certainly seems to have kept the engine oil clean, I had expected to have pulled the engine down a long time ago and done piston, rings and bearing but I am not complaining at the longevity of the engine and its almost Japanese like durability.

Moly works best as a friction reducer on ferris metals only so probably wont help white metal bearing or aluminium piston to bore wear but would help in the lifter and rocker regions of the motor not to mention the oil pump, unfortunantly here in NZ it's as scarce and hard to get as an honest politician and the only way I can get it in a pure paste form is from the USA.


Graeme
Click to expand...

Graeme,
you've got huge mileage out of your V8: what oil have you been using ? You added Nulon 30 at about what mileage ? I've had great results with ( Canadian ) Molyslip additives including an AMC V8 that was eventually retired at 550,000 miles with a cracked block :wink: LOL! Would've been the same motor as your Hornet but in a '60 Ambassador Wagon....

GW
 
Great engine the 327 AMC quite a performer for a US car of the day, a high compression engine with a 4 barrel carb and it still returned 27MPG at speed on a trip, I sadly miss that car! only about 3023 of them ever built, far better quality than the GM and ford US rivals, I will have a look in my records for the date and KMs that I added the Nulon, I think from memory it was just after the Cam and rocker change +1000 KMs so that the new parts had time to bed in and I know I have that invoice on file.

Graeme
 
As much as I agree with what you say about the formidable AMC V8, a very well engineered and sturdy performer, right up there with the venerable Chrysler RB imo, I would like to take the liberty and bring this thread BTT for a second.

The engine is back together and oiling. After twenty minutes of running very nicely for a change, it developped a bad misfire.

Ripped everything apart again and found the exhaust tappet of the rearmost left cylinder had collapsed. I took the chance and replaced it with a new one. Put everything back together and the engine fired up nicely and ran smooth on all cylinders, but there was a coolant leak from underneath the inlet manifold.

Ripped everything apart again and found, that the bolts, which hold the coolant return pipe from the heater matrix in place, had slackened, and this is where the coolant leaked. Retightened these bolts using sealer and fibre washers. Put everything back together and the engine fired up nicely and runs smooth, no coolant leaking, but there is considerably less oil pressure than before the whole operation started. In fact, the oil pressure goes all the way down, when the car is taken on a motorway for a few minutes.

My theory: There was absolutely no oiling to the rocker shafts before. The galleries were totally blocked. Hence the oil pressure was unusually high. The oil starvation of the rockers led to the rocker shafts being severely worn where the rockers -errrr.. rock (?), i.e. they are literally stepped in these areas. I think that once the revs go up and stay there, there is so much leakage oil caused by these worn out shafts, that the oil pressure drops into neverland. Hence my next step: Replace rocker shafts with good ones. Currently there is an offer on fleabay for two new rocker shafts and 16 steel rockers for 66 quid. I may go for that.
Oh, and the camshaft doesn't look like a rosegarden either, but a replacement kit is 120 quid from the Rimmers clan, which I don't have to spend atm.

On a side note: after you torqued down your inlet manifold bolts, don't forget to torque down the two bolts of the clamps which hold the tinplate manifold gasket in place at the front and rear of the engine, unless you are keen on mopping up the oil spillage off the floor of your workshop after you fire up the engine when you had forgotten to do so.
 
I think your theory for why your oil pressure was high originally and now isn't is entirely credible. But so is worn mains and big ends being disguised by the lack of top end oil. Before we go any further I think we need to know what actual pressures you are getting. The Rover V8 is known to tolerate extremely low idle oil pressure. It's not right but it will still run reliably. 5 psi at idle when hot is common. So don't panic too much. Let us know what yours is showing first! Whilst changing the rocker shafts etc might seem like a simple solution, don't forget that that will involve resetting the follower pretensions. You should have already had to do this on the one where you replaced the pushrod - all the rest too if you muddled the remaining push rods up between positions?

Chris
 
when I changed my rocker shafts back in 1989 they were as you have discribed, however my oil pressure still read 30 psi when hot, off idle it still had at least 1/3 deflection, in fact there was no readable difference between new and old severly worn shafts.

Graeme
 
Junkman wrote,...
Currently there is an offer on fleabay for two new rocker shafts and 16 steel rockers for 66 quid
Click to expand...

Hello Junkman,

Be very careful of steel rockers for the RV8. Apart from being noisy, much more so than the aluminium alloy OEM assemblies, they are also a rather loose fit on the shafts with the end result being your oil pressure will still show less than you would be hoping for.

There are also many rubbish parts available for the RV8, pattern parts with little in the way of QA. When ever possible, always buy OEM. Much more expensive but so much better.

Worn rocker shafts will indeed reduce oil pressure as you described. The undersides become heavily scored and the oil runs out as if poured through a seive. As Chris pointed out, worn shells can also contribute to oil pressure loss, as can worn camshaft bearings and a worn oil pump gear chamber within the timing cover. The oil pump gears run extraordinarily close to the inside surface of the chamber, and this close proximity is essential in maintaining good oil pressure. With oil which is left unchanged for longer than in should be, grit and other nasties can either become imbedded within the aluminium alloy chamber surface or result in scoring of said surface depending on particle size and configuration. Chipping of the oil pump gears can also occur. Another reason to regularly change engine oil and filter.

There is also the possibility that the oil pressure transmitter is at fault. Coincidence I know but stranger things have happened. We afterall are discussing a Rover... :LOL:

Ron.
 
SydneyRoverP6B said:
As Chris pointed out, worn shells can also contribute to oil pressure loss, as can worn camshaft bearings and a worn oil pump gear chamber within the timing cover.
Click to expand...

The oil pressure was extraordinarlily good. Then I freed up the lubrication to the rocker shafts, which was completely blocked both sides. The rockers are now oiled, which they weren't before, but the shafts have excessive play. Since then, the oil pressure is significantly lower. I just cannot believe, that freeing up blocked oil passages to the rocker shafts can at the same time suddenly wear out bearing shells, camshaft bearings and oil pump gears. I am not saying it is impossible for such a coincidence to happen, but I have serious doubts it has happened in this case. Worn shells, bearings, or oil pump gears would usually lead to a gradual drop in oil pressure, not a sudden one after you free up blocked passages to worn out rocker shafts.

SydneyRoverP6B said:
There is also the possibility that the oil pressure transmitter is at fault. Coincidence I know but stranger things have happened. We afterall are discussing a Rover... :LOL:

Ron.
Click to expand...

The way things are going, I believe the car is jinxed or haunted. Maybe I should call the preacher man in to excercise some excorcism.
 
Junkman wrote,...
Then I freed up the lubrication to the rocker shafts, which was completely blocked both sides. The rockers are now oiled, which they weren't before, but the shafts have excessive play. Since then, the oil pressure is significantly lower. I just cannot believe, that freeing up blocked oil passages to the rocker shafts can at the same time suddenly wear out bearing shells, camshaft bearings and oil pump gears. I am not saying it is impossible for such a coincidence to happen, but I have serious doubts it has happened in this case. Worn shells, bearings, or oil pump gears would usually lead to a gradual drop in oil pressure, not a sudden one after you free up blocked passages to worn out rocker shafts.
Click to expand...

I agree. Unblocking the oil supply to the rocker chafts won't in itself suddenly see all of the above that you listed suddenly wearing out. I never said that it would. Rather oil pressure loss can be a combination from many points as listed. The reduction in oil pressure that you now see having freed up the oil supply to the rocker shafts is almost certainly a function of the wear that they exhibit. As I pointed out, the undersides of the shafts will wear where the rockers operate resulting in excessive play as you have noted,...and a loss of oil pressure will result which is what you are now seeing. Fitting new complete rocker assemblies will restore the oil pressure to a more satisfactory level.

Ron.
 
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