Engine work needed

[bobtills]

Mr Daimler's been to see the doctor.

I've always said there is a knock in the engine especially when cold and he uses water, so after a thorough wash-down and an equally thorough inspection I have the verdict.

The engine is basically sound - the sweetest one he knows, he says

Neither he nor any of his mechanics can hear the knocking, or tapping, that I can and neither could the MOT tester or another V8 specialist so I guess if it does indeed exist it's nothing to worry about. It's probably me. It usually is.

But there are issues - a core plug (apparently there are 2) at the back of the engine is weeping, the right hand cylinder head gasket is leaking - you can see the bubbles now he's been cleaned - and almost everything that holds the rear of the gearbox on is missing !!!

So he's booked in but in the meantime I have some homework to do.

I've read and heard that there are some very inferior cylinder head gaskets to be had - does anyone know where I can get good ones?

I've decided to renew the exhaust downpipes and the section that joins them under the front of the car as they are leaking and the downpipes are a bit past it and cutting them off will make it easier to undo the manifold bolts - does anyone know where I can get good ones?

We will renew the drive belts and the water hoses while he's in bits and I have decided (after help from a previous post) to buy the silicon ones with the dull finish but does anyone have any advice as to where to get good quality water pump and alternator drive belts?

[classiclife]

Hello Bob,

I had a similar situation with what appeared to be a head gasket issue. As you mentioned, I could also see bubbles but after some investigation I found that the small length of rubber hose that connected the cylinder head coolant pipe to the thermostat assembly had a minute leak. I was only able to detect this by using a small inspection mirror positioned under the hose and sure enough every 30seconds a drip occurred. This tiny amount of coolant ran down the cooling pipe and dropped on to the cylinder head. As the engine was hot the fluid bubbled, hence thinking gasket issue.
Of course you will not see this until the thermostat opens and by then the cylinder head is hot causing the bubbling. I replaced the small piece of rubber hose and that solved the situation. See photo - you can just make out the thin blue line of coolant.

It may well be the case that your bubbling occurs immediately and if so then yes suspicion has to fall on the gasket. But the above point is certainly worth checking if only to eliminate.

The single layer steel gasket (SLS) is the correct item and NOT composite. The SLS items supplied by DMG or SG-B is spot-on. One point worth mentioning is that the head does NOT need re-torqueing, once fitted and tightened correctly that is job done.

Cannot assist with the downpipe and balancer pipe and I do not know if the usual Daimler suspects supply the sections individually. Quite often it is the whole assembly that is sold. One issue you will find is that the exhaust manifold studs to downpipe are too short if you are using the crushable sealing rings - see photo. Historically it was an asbestos type gasket or something similar. When I refitted my downpipe to the exhaust manifold, it was necessary to do the above; fortunately the manifolds were off the engine at the time hence a simple operation. See photo.

I use Gates V belts for my applications on the Daimler - excellent quality; just take your old belts to a motor factors and they will measure the belt for you and provide the replacement Gates reference number.

Hope the above is of assistance.

Regards.

Richard.

[bobtills]

Thank you Richard - I've heard so many horror stories about inferior parts being fitted and failing very quickly it's good to have advice 'from the horse's mouth', so to speak.

My own experience with a condenser from one of the big suppliers which failed after less than 200 miles and left me stopped at the side of a very busy dual carriageway (fortunately I had the old one in the boot but it wasn't much fun changing it at the side of the road) makes me seek advice from those who have had success in sourcing parts from now on.

I've looked at exhausts and as you say, most want to supply a whole system which doesn't suit me as the rear is already stainless. And 2 stainless downpipes cost nearly as much as a whole system, which is a bit daft.

I've found some downpipes and mid-section pieces on DM which are much cheaper and I guess are mild steel so I'll give them a call. I hope they also have the balancer pipe as mine looks Ok but blows through the flexible section.

[classiclife]

Hello Bob,

If I were running the conventional points set-up on my Daimler, I would not touch any of those components from the well known names / outlets. My only route would be via Martin Jay the Distributor Doctor; hence the offer I flagged earlier in the year for an ignition package for V8 owners which proved very popular.

Best wishes.

Richard.

[bobtills]

Wish I'd seen that!
It was the Distrubutor Doctor to the rescue for me - and what a difference! So much smoother and so much power - like a different car after fitting his condenser

[classiclife]

Excellent to read that, Bob.

The offer was for a red rotor arm, 2x sets of points and condenser - all constructed by the DD.

Package was sold at cost / wholesale plus p&p, being 50% less than over the counter price. I obtained 25x ignition packages and needless to say all gone within 14x days !!

It is an offer I will put forward again, at some stage.

Regards.

Richard.

[bobtills]

Another 5 weeks or so before the work can begin but in the meantime I have noticed something a bit odd.

The oil pressure had dropped a bit and a slight rattle on right hand bends had developed - like on a roundabout

So I checked the oil level and it was just on the bottom of the hatched area. I topped it up and the pressure came back but the rattle is still there when cornering - nothing much but quite distinct. I read somewhere that these engines can develop faults which are only noticeable when cornering but I can't remember where, or any more about it - can anyone comment on this?

And as the oil pressure had dropped with the oil still touching the bottom of the hatched area, well up the stick itself and came back when topped up, is this normal? Do I have the wrong dipstick? Is the SP dipstick shorter perhaps? I know that the oil pressure sender can deliver wrong readings (and that's on my list) but that won't explain what happened.

[DAIMLERMAN100]

so it,s DMG for quality head gaskets then what about piston rings and bearings ?

[bobtills]

Well, it's been a while but we have progress:

Both head gaskets were blowing, it had been burning a lot of oil (I couldn't tell because it was leaking so much), and blowing coolant out (which I did know) and the pistons were loose (actually wobbly!!) in the bores and badly scored. The bores themselves weren't too bad (no scratches but varying up to +2 thou ovality).

The engineer recommends a rebore and as the bores are already +20 thou and his suppliers don't do +30 pistons, +40 will be the final size. +30 pistons are available from the usual suppliers but I have read that there are problems with the rings not being the correct size (so gaps are wrong) so after he assured me that the +40 pistons he could get from his suppliers are guaranteed to be spot on I told him he would have the final say about that, as about most things we discussed, as at the end of the day he's the expert, not me.

We decided to renew the crankshaft bearings while we were at it and he can get all the bearings but only bi-metal ones - are there and better ones available anywhere? The journals are Ok and he'll just polish them.

The little ends were badly worn (after only 15,000 miles!) so they will be changed as well.

The valves had lots of carbon on them so although they don't seem to be worn the guides will be changed - or isn't there an upgrade kit for these that stops it? The valves and the seats are Ok.

The heads don't have any noticeable damage but he wants to skim them because both gaskets had blown (they've already been skimmed once).

So, any advice anyone - pistons, bearings & valve guides? Or anything else really

[bobtills]

We have the engine back and ready to fit in the car. The gearbox was given the once over as well - an opportunity too good to miss!

I have a box of 'stuff' which has been replaced and I wonder if anyone might have a comment regarding the 'rope' seal that has been removed. This is the rear seal, which was leaking, and I was wondering if anyone could comment regarding it's shape. I would expect the 'wearing' surface to be a bit flat but how does it look to you? The front seal wasn't leaking and is much rounder than the rear one. My apologies for the poor photo but it's the best I could get.

The new one was fitted using the correct tool obtained from J & E Engineering so it should be sorted