Whats wrong with it - V* Diesel ??

Don Wyatt

New Member
Hi, just bought a cracking 3500 V8, she has great oil pressure, and pulls like a loco, the problem is i suspect there is something wrong. Basicall she sound like a london cab, on tickover, and when driving/accelerating, once you get up to about 60mph she is okay (this may be just that you cant here it so well, I dont know. Its not a knocking as such, just a very evident loud ticking, as I said just like a london deisel cab, any ideas. as i dont think its normal, I mean its a big engine, and i dont expect it to hum like a sewing machine, but ????
all help appreciated.

Don (the mechanical donut)
 
Hi Don,
Does the ticking noise come on after the engine is warm (loose sleeve), occur at startup and diminish (bad lifters and camshaft), or begin at startup and remain constant (exhaust leak near the engine)?
 
Try and buy some belt dressing and spray on the fanbelt. Failing this use a small spray of WD40 but not enough to make the belt slip.
The belts often make noises similar to noisy lifters etc. It's surprising the sorts of noise they can make, and it's so easy to eliminate them as the cause.
 
Would agree with the others and say knacked lifters.
Either live with it or pull the heads off and change them may as well spend the extra on a set of rhodes lifters whilst you're at it though.
Have fun setting the preload... :p
 
Thanks guys, It tends to be noisy right from the start, and today I had it ticking over for a long period, and it got worse, then all of a sudden it dissapeared. It seems to be coming from one side of the engine more than the other, or side only, its difficult to say exactly but one side is definately louder.
I will try the WD40 trick on the fan belt just in case, but it does sound more like its in the engine. A friend listened through a large screwdriver and he said it sounded like the tappets or cam, though he's no expert.If it is the tappets or cam shaft are they easy enough to get hold of?
 
How do i post some pics of my P6, please give me the fools version. I tried the image button but it says I must enter a URL ??
 
heh, bits for the Rover V8 are about the easiest bits to get for these cars.
I'd go to a company that specialises in the RV8 though.
RPI, Real Steel, V8-Tuner heck if you're desperate rimmers!

If you;re changing camshafts then dump those useless nylon timing chain gears and go for duplex vernier timing gear.
Personally i'd go with a 3.9 cam and rhodes lifters which bleed down at lower revs improving the economy and enabling you to run a cam with a slightly more lairy profile and still maintain an acceptable idle.
 
The V8 is partial to a nice camshaft for lunch, especially if its been run past the oil change mileages.

Camshaft is easy enough to change - its in the top of the V and visible once you take the inlet manifold off - but make sure you change the followers at the same time, even if they look OK. Old cam followers will take out a new cam. Good advice on a duplex chain too.

Then make sure you change oil and filter every 3,000.

My instinct would be to run it for a bit until it starts missing through lack of valve opening! Then do a proper rbuild.

Chris
 
Thanks Chris, It is already missing very slightly, so when you say full rebuild, what else do you mean other than Cam, followers, tappets and chain. ?
Or is that it. ?

Sorry im a basket case when it comes to engines.
I have a really good mechanic (old school) I can get to do the work, but I dont want to look like the pleb with an open wallet if you know what I mean.
Don.
 
OK, Well you already say that oil pressure is good, so the implication is that the crank and rod bearings and oil pump are pretty good. Next information required is to do a compression check and compare to book values. If OK then action is limited to cam and followers and duplex chain.

If not then you need to identify whether the problem is rings or valves.

If one cylinder only is down then it's likely to be either a valve or a defective ring. If the latter then I'd expect to see some evidence on the bore and / or high oil consumption.

If the readings are generally all over the place then something's tired. Once the heads are off look for excessively polished bores together with high oil consumption, if not then probably just valves.

Once the heads are off for either of valves or rings establish whether you have P6 or SD1 heads Easy check is to measure the valve sizes - SD1 are bigger). If the latter then just send them off for overhaul (skim surface, new seats, new valves, new valve guides etc) making sure you specify you want them back unleaded so you can use normal petrol. If they are P6 find someone (like RPI but there are others) who will service exchange them for SD1 heads.

If you positively identify that the problem is rings I wouldn't mess around - I'd just get a service exchange "long" engine (ie including heads) to the spec above.

From what you've said I'd expect to find the problem is just cam - but I'm not in front of the car!

So next steps are to drive it for a bit and see what the oil consumption is like. To be wrong we're looking for it to use bucketfulls too much not just the odd half litre! Then get someone to take the cylinder compressions for you and report back here and we'll move on from there!

While you're at it do a simple service - new plug leads, distributor cap, condensor, points and plugs and change the oil and filter. Just to eliminate the ignition system as a cause of the misfire; won't do any harm and might do a lot of good!

Note the relaxed attitude - you are very unlikely to do any harm running as is, so take your time!

Regards

Chris York


One other thought: the V8 is quite prone to electrical arcing out of the plug harness and in the vicinity of the distributor cap. The service is intended to address this but the other thing you could do would be to have the bonnet up at night down a dark country lane (No NO NO!) and watch for the blue fllashes. They can often sound surprisingly loud as ticks or knocks.
 
The V8 is a great engine but does suffer if the oil changes are neglected. Very rarely do they need a rebore, and in view of the graded pistons fitted from the factory I would never rebore one.
A quick list of items to replace would be rings, end and main bearing shells, camshaft and followers, pushrods, rockershafts, posts and rockers, timing chain and gears. Along with oil and filter, and all gaskets and seals away you go.
Take the opportunity to upgrade to SD1 spec heads at the same time, and if you want a little extra horsepower at no extra cost fit a 3.9 camshaft.
 
CRIKEY FELLAS, didnt expect that much advice, Brill.
I will print this off and show my bloke, Im sure he will know what you mean, (unlike me, ha ha)

Thanks ever so, im just off outside to take a look at the old girl running in the darkness.

Don.

Ooops no im not is 10 to 11, maybe tommorow.
 
Hi Don,
First, I agree on the 3.9 camshaft being a good one, but feel the Rhodes lifters are not necessary. The profile of the 3.9 lobes is identical to the 3.5 lobes. The cam has only been advanced to improve low end torque. Save the Rhodes lifters for a cam with more lift. Do use a true roller duplex chain and new lifters (tappets.)

The V8 has a great many internal leaks and the oiling system is designed to pump a large volume of high viscosity oil at relatively low pressure. When rebuilding, it is essential to keep clearances proportional. You cannot simply replace the main bearings and connecting rod bearings without replacing the cam bearings. If you do not replace the rocker arms and rocker arm shafts, you will need to install oil restrictors in the block deck or heads to keep the oil in the bottom of the engine. I have seen too many Buick/Rover V8's that have been "rebuilt" and lasted less than 10,000km because the top end of the engine was left "loose" (old rockers and shafts and no oil restrictors.)

Other than this, the rebuild is quite straightforward.

Kent K.
 
Before taking any more drastic action definitely first check for exhaust leaks from between the exhaust manifold and head, and between the manifolds and downpipes.

One of my old 3500S's had less than perfect exhaust manifold studs that wouldn't allow a firm manifold to downpipe joint. The leak then became progressively worse and sounded very convincingly like a ticking tappet.
New manifold studs and brass nuts soon cured that. :)

Also, a smear of General Purpose Silicon Sealant on the mating surfaces of the exhaust manifolds should provide a good seal if your not using gaskets.
 
Well thanks again everyone, I checked the engine running in the dark and there are no blue sparks anywhere, so that that eliminated.
Could someone tell me, On ebay theres a chap selling a cam, and a duplex chain and gear, he sayshe will throw in the tappets too, could someone kindly check these bits out for me and advise if there gonna be okay for my car.
Or should I buy new. ??
Again, yours very gratefully.

Don.
 
Don Wyatt said:
On ebay theres a chap selling a cam, and a duplex chain and gear, he sayshe will throw in the tappets too, could someone kindly check these bits out for me and advise if there gonna be okay for my car.
Or should I buy new. ??
Don

The rumour that early Rover camshafts were made of soft cheese has been demonstrated to be an exaggeration. Recent studies show that in fact a hard cheese matured in caves in the Pyrenees was used for many years until EU regulations required valve train parts to be pasteurised

Buy new and save yourself a lot of potential strife: a camshaft on a Rover V8 is really a consumable item, though a reasonably long lived one.

Unless you can inspect the parts yourself or have someone knowledgable do it for you, you well may find that the used parts are no better than what you are replacing (especially when trading on evilBay).

Aidrian
 
Yes thanks for the "cheesy" advice. this has been echoed by my mechanic, its new I think, apparently a kit with cam and16 tappets and gaskets are about £120 from Wadhams.
 
Hi again all, (Happy New Year Everyone)

My "really good mechanic" seems to have done a lord lucan, tried to make contact and he has not come back to me.
Maybe he isnt too keen on working on my V8, Who Knows?

So, can anyone reccommend a P6 engine specialist please in the south east, I would like someone professional, who can listen to the engine and know just what the problem is, and then fix it. (simple eh) or...............

Any ideas please gents.
Don.
 
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