1968 Daimler 250 v8 - Moving on

I get presented with stuff like this a lot. The problem is without doing machine work there's no way to telling what will be needed so I'd suggest:-

Firstly get the block pressure tested or make a kit up to do it yourself. Easiest way is to get some smooth surface rubber mat, punch the head bolt holes out then bolt the heads back on with the rubber inplace of the head gasket. Blank any other waterways off then drill one of the blanks so you can screw a airline fitting in to fill the water jacket with pressurised air. I usually try and go to about 60psi (I assume you have a regulator with you doing your own paint). Tip the block upside down then fill the cylinders with hot water and look for bubbles.

If that checks out OK and corrosion hasn't eaten through the cylinder wall:-

Find out what the biggest oversize pistons available are, and also there may be a 'safe' limit that is smaller than the biggest oversize available (usually due to heat transfer issues or core shift in the block).

Take the block to a machine shop and get them to bore the heavily damaged bores to the required size. I usually go about .003" under the required size (instead of .005-.007" on non corroded) as it if the damage isn't gone by that point then you can move onto the next bit without wasting time honing.

Find out if cylinder sleeves are available. I like Westwood Liners they've got a decent range. If they are then the damage can be repaired. However there is a big (expensive) but....I'd put a small to medium wager on it still needing oversize pistons. I often get people asking me to sleeve one cylinder back to standard. However when the sleeve is fitted correctly in 90% of cases it distorts the adjoining cylinders, meaning they then need oversizing to make them round. It will mean the oversize required for the pistons will be smaller (probably get away with +10 or +20) but I'd imagine the cost of pistons is roughly the same.

The heads will probably need guides or K lines then the valve seats recut unless they've been done recently (mileage wise).

Looking at the colour of the cam it's gone through the surface and is bin fodder.

Followers is something I've not had experienced of and a solution sounds difficult, but they definitely look knackered.

Get the crank polished and measured. A few speed lines in the surface won't hurt anything as long as its on size. Fit new bearings, it's odd that the mains are on the copper and the big ends aren't though, big ends might have been changed before.

I'd imagine the oil pump will be pretty bummed, worth checking if replacements are available.

Ahh the Glacier Grenade, 7 second Rail, who built the supercharged A series rail that ran 7s too, sorry for the Hijack

John Whitmore was the guy who built the A series dragster.

Thank you all for your advice and thoughts As I mentioned engine swaps are off the cards, so let's just close that door on the options list! I really would like to finish the car and get to drive it, the reason I've worked so hard and intensively on it over the past year is for that very reason. But I cannot say that sinking further money into this build, and it already owes me more than any car I've owned, isn't daunting. There's plenty of time to think about it and fully asses the parts I've got while we wait for life to return to a bit of normality.

homersimpson I also started off by digging out part numbers from other suppliers and attempting to plug them into the DMG website when they first swapped over, and likewise I've also given up and recently have just been using SNG. That said, when there are hundreds of pounds to be potentially saved... I'll happily put up with a slightly dodgy website! As DMG is only 20 mins up the road (under normal circumstance) it's not a big deal to drive up and ask over the counter, where their staff have always been friendly and helpful.

Thank you for the link to the pistons. I'd already tried to find the pistons on their website, but the listing for standard sized pistons takes you to a plan page with a price of £0, and I didn't think to try any of the oversize options! £490 is a lot closer to the £400 it would cost for Triumph pistons, and therefore much more tempting, especially if +60 oversize would mean I could avoid needing to have the block sleeved. Realistically some of the pits in cylinder L4 are really deep, so I suspect it would be a case of whether I could get away with 1 sleeve instead of several by going upto +60.

darrenh Yes I think you're right there. In my excitement to see just what was hiding inside the engine, I didn't release the pressure on the valves. I presume it should still be that the rocker pedestals come free before the head gasket releases, but due to the corrosion on the dowels this didn't happen.

Flynn thank you for the recommendation of a machine shop. More recommendations is always good, and I'll look int that and the recommendation from homersimpson from earlier I the thread when/if the time comes. I like the analogy of the food shops

ivanhoew it's certainly my plan to keep stripping this engine down and will measure and check every part as I go, before I make a plan as to what to do. It's hard ot see I the pictures, but I believe the pitting in the L4 bore is severe enough that it would never run right with it just cleaned up and put back together. I didn't mention before but when winding the engine over by hand the pits in the bore of l4 would fill with oil each time the piston passed over them, and this is why I think the exhaust was running wet with oil. It could be that the rings are stuck on just this cylinder, and if that's the case maybe it's worth considering the cheap and cheerful options to at least give me a chance to drive the car for a bit, possibly while building another engine in the background.

I'm normally up for a maintenance rather than restoration approach, as commented earlier I the thread, but in this case I'm a littler concerned that I could still spend several hundred on bearings, gaskets, oil pump (which it will probably need) and fluids to end up with an engine that's still not right. Worse still if I try to polish the scores off the cam and then it chews itself up again now it's lost it's hardened skin, will that spit lots of little bits of metal shaving back into the oil and take out the new bearings all over again?

I'm not at all closed to the idea of some kind of cheap get me going option, but I don't want ot end up just making more work/cost for myself.

crockpot I've been eying up all the second hand engines that I can see and I had seen that one for £900 on eBay, but thank you for the heads up. £900 is a lot to spend on a roll of the dice. This very broken engine span over freely, made some reasonable cold compression and would start up and give good initial oil pressure readings. It wasn't till I drove it that the big problems showed up. So any engine I buy could be just as bad. On the other hand, that £900 engine could just need the sort of strip down and clean up procedure Robert was suggesting and could be a great option. It's just a big gamble.

Thank you stealthstylz for the detailed reply from experienced eyes, I shall bare it all in mind when speaking to a machine shop in future. When I have stopped the block down I will do the pressure test as suggested The good news own overbearing is that you can go a long way, I believe sonus is taking his out to +0.150" to gain capacity. +0.060" seem to be the biggest off the shelf pistons I've seen. I've been trying to think if there's a way to measure the depth of the pits (without special tools!) to get an idea of whether it's likely that a 0.060" overbore would be enough. Maybe I can use some plasticine or something to take an impression of them. Regarding the cam, if I were to go down the route Robert suggested, and put together a temporary cheap engine, and I polished the worst of the scoring off the cam and followers, do you think it would likely score up again and cause problems with debris in the oil? Or would it just wear at a bit of a faster rate than normal?

Yes I am going with .150 overbore. Had new pistons cast in Argentina to fit and to raise compression to 11:1 static. Will be much less dynamic compression with the chosen cam profile 👍

I'm pretty sure there is some form of 'spray on' metal finish for building up followers etc that might save them. No ides of where or how much though.
I would think a cam specialist could grind a new cam for you as well.

As I said, I would have a word with Ken Newman, very helpful and knowledgeable.

Not sure if this has been mentioned. If your gearbox wasn't set up properly they rapidly overheat. If the cooler for the transmission is part of the engine radiator it will overheat the cooling system. I had this on a car once knackered gearbox and nearly killed my engine.

I don't think tuning is the dark side sonus, surely making it faster is seeing the light! Some lovely mods there on your build. The Type Y cam followers look a nice fit!

On the cam followers front I'm pleased to say that I've been mislead by old sources, and that new cam followers are available from the usual suppliers, DMG etc. They're not cheap, but a lot cheaper than having old ones refurbished would be I'm sure.

If I went down the modern electronics stuff in the future, I'd like to try a Speeduino ECU. It runs on the same softwear as Megasquirt, which I'm very familiar with, and whilst it doesn't have the flexibility that Megasquirt has, it would do everything I need of it.

skylinedave, I saw that block and did consider it for a bit. But without going to see it in person, which I wouldn't consider an 'essential journey' right now, there's no way of telling that it's any better than mine. Pictures of oil and dirt covered bores could easily be as bad as mine. On one of the photos you can see one of the main bearings looking worn right down to the copper, same as mine are, so it could easily be as bad. This is why it's such a gamble buying these parts online. I can't se a full engine for £600? The cheapest full engine I can see is £900 and it looks pretty corroded on the outside, and again without closely inspecting it in person it could be just as bad as mine or worse.

That's an interesting point wildy . I think from what I've seen already of pulling this engine apart, I suspect the blocked passages in the heads and block were the root cause of my overheating, but it's always possible the gearbox wasn't helping matter.

I've been carrying on with my autopsy over the past couple of days, and its been a pretty mixed bag and finally ended with a bit of a shock. I got the timing chain and bits and bobs off the front of the engine, all of which seemed in fairly good condition. Like the rest of the internal components of this engine, there's very little oil staining and soot which is interesting. Almost all of the second hand parts I see are jet black with oil sludge and staining!

With the timing stuff off I could get the cam out and have a proper look at it. It's not quite as bad as it seemed from the first pictures I don't think, not all of the lobes are in such bad condition and the bearings and journals look alright. Still it would clearly be silly to try and reuse it.





Looking into the valley with the cam removed I could see just how much crud was in there, some if it being big old chunks. Those black bits next ot my glove are solid flakes.




I couldn't say what the chunks are, they could be rust flakes or they could be carbon? Either way, I suspect this is what's gone through the engine causing all the scoring damage I've seen. Given how clean the rest of the engine looks, I wonder if a previous owner used some oil flushing type products without realising there was this large oil bath in the valley? And therefore leaving this big chunks of carbon/debris behind?

Digging in to the bottom end, I was preparing to start marking up the con rods to make sure I know which way round they go, when I spotted that they were all stamped with their location, and handily this also tells me which way round they go and keeps the rod caps the right way round too.




Pulling the pistons out, they looks 'ok' but quite worn to me. All the pistons look very alike with light carbon on the top, all rings looking undamaged, clean and free. I can only compare them to rings out of 2 strokes (as that's my main engine work experience) but I'd almost say they look like they've been replaced recently? You can also see from the size and chunky-ness of that rod, why they can take the power they can! All of the pistons and all of the bores measure up as close enough to standard that I believe they're original, which at leats means there's room to bore the block out to oversize still.




6 of the big end bearings had scoring like this one, which is clearly debris in the oil and I would suggest is very recent as the damage is confined to the area directly above the oil hole in the crank journal.



All of the big end bearings are stamped VP which, from what I've read, suggests they are original. Likewise the front and rear main bearings are stamped VP but the centre 3 main bearing, which are the heavily worn ones, are stamped VP STD. So while they are the OE brand, it makes me think they are replacements?



Moving on to the crank, the journals all look 'ok' to me. The oil was very brown and dirty under some of the road bearings, actual dirt/rust rather than old oil.



This surprised me as when I bought the car the oil was very clean looking, and I had since had the sump off and through cleaned it out before refitting and filling with new oil. Maybe the engine had corroded inside the oil galleries, and that's what's spitting debris into my bearings and killing them?

I haven't got as far as checking the sludge traps in the crank, but it's on my to do list. I imagine they're full of debris also.

Anyway wiping the oil away there's some light scoring on the crank, most of it I couldn't feel but across the centre where the oiling hole of the worst couple of journals I could just about feel something with my finger nail. I believe it would polish out? Here is a picture of the worst journal.



I did attempt to measure the journals but I'm not sure my digital 'micrometer' is upto the job. I measured them all as 0.003" - 0.004" under, which according to my manual is just past the wear limit. But I got the same 0.003" undersized measurement when I measured the sections of the journal that the bearings didn't run over, which suggests there's no measurable wear? It could well me that my cheap digital micrometer isn't accurate enough really. Or if could be that in the past someone's polished the crank down to this size? On the positive side, regardless of the exact numbers, I could tell that they were all even and showed no signs of ovality. So would hopefully be no problem to have it ground 0.010" under if needs be.

Moving on to the oil pump, removing the cover I didn't see lots of circular scoring on the top lid or top of the pump gears, which gave me a bit of hope. But I think the straight lines scratches suggest that someone has tried to give this pump some extra life by sanding down the body and gears to tighten up the clearances. The pump gear to top cap clearance was still past the wear limit anyway.



Then removing the gears showed that the pump body was heavily scored inside along the walls, and also had some rust. So I believe this pump is only fit for the bin (or being given in part exchange for a refurbished one I guess!)



The oil pressure relieve valve was also rusted and scored.


So by this point I'm thinking "this all looks curse word', but it's still just a case of wear and not catastrophic failure...

And then I spent a long time with various wire brush pipe cleaners and a hose pipe trying to clear out all of the crud from the cooling jacket around the cylinders, which was a lovely fun job. I didn't get any pictures but, as you can imagine, there was serious amounts of crud wedged in there. When I'd got the worst of the crud out, it would need another session to get the last of it out, I gave the whole block a bit of a once over and clean down. Immediately a spotted a rather big problem.



No idea how I didn't see that spectacularly big crack before. I think it must have been covered over with corrosion and remains of the head gasket. I'd say looking at it's position, that it's frost damage. The freeze plug next to it was pushed almost out of the block and looks to have been leaking a little.

So thats really bad news. I think this might be the straw that breaks the camels back. The extra cost of trying to have that fixed, if it's even fixable, might just tip the tables on the economic viability of continuing with this engine. I'm starting to think that looking out for another engine/short block that 'only' needs a light refresh (bearings ,rings hone, etc) rather than this level of deep rebuild, might make more financial sense.

As mentioned near the top of this post, in order to judge that I'll clearly need to go view the engines in person, rather than relying on some eBay photos, so I guess that's gotta wait till the lockdown is lifted. Even then it will be a bit of a gamble.

Still I've got plenty of time to mull over my options I guess! For now I'll just shut the shed door and mope! Anyone wanna swap a stupid broken old Daimler for a car that actually works?