Engine overhaul

[Manfred]

After a long time of preparing I finally know what is the most sensible thing to do with my car. My engine is getting very tired and needs replacement. Because it is my only car I can't miss it to long so overhauling my own engine was not an option. Also the gearbox is getting worse and worse the last year so that also needs attention.

At the beginning I wanted to place a bigger engine, but cue to a lack of good used units that option also fell of. In the end I found myself a used 3.5 engine out of a 101 fc. The owner wanted to place a diesel engine so the V8 had to go.

Today I started with putting the engine on a stand and to disassemble it.
After removing rocker covers and inlet manifold I was pleasently surprised. It was all shiny and clean, seemed like a new enginge!
To check it further I did a compression test. This showed the engine wasn't that new. 3 cilinders showed only 7.5 bar where the others did just over 10. The v8 repair/operation manual says it should at least be 9.5 bar on every cilinder and a maximal difference between the cilinders of 10% so my figures are not acceptable. With a drop of oil on the pistons it was better overall, but still the same pistons were problematic. Knowing this I think the problem does not lay in sticking valves.
After that I removed the heads, timing cover, push rods, tappets and camshaft.

The plan is to check and restore cilinders, place new piston rings, crackshaft bearings, new camshaft (anyone who has experience with "preformance/torque camshafts" like piper etc?) and have the heads done.
Will probably replace the ZS carbs for SU if I can find a pair and LPG insert rings for them.

I am planning on making pictures during the proces and placing them on my picture website. http://manfred2266.fotopic.net/c266670.html
The pictures of today are already on it.

I bet others have already done an overhaul, so if anyone has worthfull tips i'll appreciate it!

[jonnyboy]

Hi,

Thats a clean looking engine. If it was reconditioned by the MOD then it would be painted.

If some oil in the cylinder didnt improve the compression test then it could mean that:

1. The bores are very worn and a new set of rings will not cure it. It will need a rebore and bigger pistons.

2. The valves could be sticking or worn. Try swapping the heads and doing another compression test and see if the problem moves to a different cylinder.

Be carefull buying performance camshafts. Make sure you get one designed for more torque not high revs. Fitting a 3.9 cam to a 3.5 is a good improvement.

Is there any wear in the rockers and shafts?

[Manfred]

Jonnyboy,

Oil on the pistons improves the overall pressure, but the difference between the good and the bad pistons I had before was still the same.
Wasn't very clear in my previous post..
I guess knowing this the problem does not lay in sticking valves

Heads look like new, rockers, rockershafts, etc seem to be very sound. I think this has already been replaced, the tappets show absolute no sign of wearing, you can't even see marks on them where the camshaft has hit them..

In comparison with the high torque camshafts, what difference does a std. 3.9 camshaft have? Will it deliver most between 1000 and 2500 rpm's? I want the power on the lowest rpm's as possible.

[Jambo]

Manfred,

If you replace the camshaft, do also use new tappets. Even though you say they look alright, not using new tappets may cause premature wear. Also, i see that you put your pushrods together in a cup. The general advise is to mark them, so you can use the rocker-pushrod-tappet as a set. This for the same reason - to prevent premature wear.
I'm rebuilding a 3.5 V8 as well at the moment, planning to convert to EFI. I have bought a duplex pre-stretched timing chain. I think that's a good investment for a recon engine.

By the way, your tubular manifolds look the business. I have been looking for tubular manifolds to fit a 109V8, but no-one can guarantee theirs to fit a 109V8. I'm afraid that having custom ones built like yourself is hugely expensive. Do you mind sharing how much this EPS-set has set you back?

Regards,

Hanno

[Manfred]

@ Jambo,

I think I will order a complete cam kit with the cam, new tappets etc. The pushrods are all numbered with a piece of tape.

The timing chain and wheel I will change also. As you can see on the picture it has quite a lot of slack.

The Stainless headers are from a 110 and needs some severe rebuilding before it will fit the steering arm. My opinion is still that it's way cheaper to do this then having one completely built.
The EPS system starts after the headers and contains one absorbtion damper. I guess it was something like €900,- and was completely built & fitted while I waited.

[Larosto]

Hi,
I`ve done an engine rebuild a half year ago. I think you should have a look at your rockershafts. Even if they look good when they are complete, they may be worn under the rockers.You can see it after dimanteling.
I renewed them in my engine inclusive all rockers. My engine had bad compression too, so I rebored it, and installed bigger pistons and of course new rings. All bearings were renewed, oilpump gears, timing chain and gears, etc. When I looked at the valves, I saw that the outletvalves were worn (pittings on each one), so I renewed them too.
At first after rebuilding, the engine had high oil and fuel consumption. (18-21 ltrs fuel per 100 km, and about 2-2,5 ltrs oil on 1000 km.
But now, the engine has done about 1500 km, it`s much better.I think oil consumptin is about 0,5-1 ltr and fuel consumptin is about 15 ltr per 100 km.
The engine runs very smoothy, starts good and pulls very good. The restrictors are out, and the original carbs (175 CD) are installed. The carbs are overhauled too.
Good tips for inspecting the Rover V8 engines are on www.v8engines.com . I hope, this helps you.

Good luck

Horst

[steven 90]

I did my engine some time ago so if ican be of some help just send me a message,i am sorry my englisch is not so good hower my dutch is fine

Groeten

Steven

[mictho]

Hi Manfred,


where did you get those tubular exhaust manifold/downpipes from? I wouldn't mind getting a pair... Also, do they break the bank?

TA!

Mich

[Manfred]

@ Steven, that's very kind of you. I think I will be fine, but if I have something to ask I will

@ Mich, The headers I have are manufactured by Tiger exhausts. They are for defender 110. Due to different steering box and axle they need some modification to fit properly on a stage one, but it can be done.

They weren't that pricey, otherwise I would never have bought them. Exact price I don't know anymore but I am sure you know it with one phonecall to them.
Engine breathes much better with them, throttle response is acceptable now even with the Stromberg carbs.

[Manfred]

Engine is at the point of reassembling again. Couldn't find the time to begin earlier..

After having measured crankshaft bearings, big end bearings, cilinder bore and pistons I found out the engine was in a very good state. Could do with std bearings, today I stopped after refitting the crankshaft.

Some new pics are on my website http://manfred2266.fotopic.net/c266670.html

Bought a complete camshaft kit from RPI. Hopefully the Piper Torque Max set will give the engine a bit more grunt in lower revs. Also the problem of stretched chains should be history now with the duplex one.


Will try to keep the foto site up to date.

[Skye Stage 1]

Wow, looks like that's going well! The duplex chain should, as you say, stop the problems of loss of timing, poor running, etc; may I ask, did you ever find out the cause of the disparity in compression figures?

[Manfred]

Not yet, I brought the heads to a professional I know. He will pressure test them and do the valves + seatings etc.
When I have them back I may have an answer to that question.

[steven 90]

Not yet, I brought the heads to a professional I know. He will pressure test them and do the valves + seatings etc.
When I have them back I may have an answer to that question.

Put new valves in I have got mine from martin motors and in belgium it is cheaper to replace the valves then to have them grinded.
Also if you grind the valves and the seats then you have to check tappet pre load.

S

[Manfred]

New valves will have to be grinded also to fit valve seats, won't they?

Well we'll see.. Think I can collect the heads tomorrow.. can't wait!
Checking tapped preload was planned already, so if any problems occure I'll see it anyway.
I'm trying to make a complete measuring report for all bearings, bores etc.

[Larry]

Saw an interesting way to clean up valves on a TV programme about motors in Bangladesh. Just put them into a pillar drill and hold a bit of Emery cloth round them while they're rotating, moving it up and down.

New valves would need re-seating/lapped in.