andyborris
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Freedom is just another word for nothing left to lose.
Posts: 2,145
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Got a Rover V8 with overheated 14 bolt heads. They'll need at least skimming, maybe junk.
Have a pair of later, better 10 bolt heads with rockers. However, I don't have all the matching valve train, only the rockers!
Now I know that you're not supposed to mix valve train parts, they should go back exactly where they came from. But I can't afford to replace valves, rockers, shaft, tappets, lifters, camshaft and cam bearings.
I can replace one section (I can afford that!), but which part? Which section of the valve train will be unhappiest at not being in it's original position?
I can reuse all the valve train from the engine on the new heads, only the valves will have a different wear patten or I could buy new tappets, but then the rockers and lifters have new wear patten.
Not sure what to do here, any advice?
Thanks
Andy
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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Or spend the money on tools and swap original engine valves into new 10 bolt heads?
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stealthstylz
Club Retro Rides Member
Posts: 14,812
Club RR Member Number: 174
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Reusing Valve Train Partsstealthstylz
@stealthstylz
Club Retro Rides Member 174
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The only bits that matter are the cam and lifters have to be matched and in order, or old cam with new lifters only, and the valves will need refacing ideally to use in the other heads. Rest of it can go wherever, just go on condition.
Whilst you've got the heads off get some timeserts fitted to at least the centre head bolt holes in the block. If it's been overheated it's pretty much guaranteed to pull the threads out of those on reassembly. It could pull others, I usually just do the centre 4 and see what happens as people don't want to pay to have them all done.
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Not a Rover expert, just a mechanical engineering technician with a semi logical thought process, if that helps.
I'd keep the same cam, bearings and lifters already in the block you have. Anything down in the block should already be worn in and happy and is best left alone as it's the most expensive single component and has all been proven to work.
The pushrods should probably be happy enough to be reused if they're straight and all of the same length (unless there's a factory difference in length between the required pushrods for different heads...)
I'd keep the rockers that are already on the new heads so long as they're free moving and not wobbly because they're the next highest stressed point and, theoretically should be good and worn in to those heads.
Your old valves will probably be unhappy in the new heads. The seats will definitely need re-lapping at a minimum. You could maybe re-use the valves if proper precision measurements could be taken of the guide bores, valve stem diameter/straightness, etc and established to be within correct tolerances.
That's where I, personally, would spend the money. Getting the valves, guides and seats all matched up to the new head. Slight differences between new/old valvestem lengths and suchforth should be able to adjusted out by the same means you set valve lash currently.
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I'd also have a good look at the condition of the rocker shafts, they're a known weak point, and can often have a serious amount of wear at the point the rockers rotate on them. I've known people turn them 180° to try to loadbear on a different section, but obviously that's just a short term solution
Edit- I've got a pair of 14 bolt bare heads here, Norfolk Cambs border, but they're off a low comp engine so I'm not sure you'd want them?
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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Thanks everyone and aren't those Wurth inserts expensive!
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As others have said as long as the cam and followers match, the rest will be OK, especially given they have hydraulic lifters. An alternative is to use studs ilo of the bolts but they are not cheap either! (ARP set is around £150).
If you do add thread inserts to the block make sure they are dead square, a tiny bit out and the bolts are a couple of mm out at the top so the head won't go back in.
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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As much as I think it's a good idea, I'm not going to fit inserts. The Timeserts are incredibly expensive, more than a complete used engine! And I don't have the facilities to remove the block to fit them, even if I use a cheaper version.
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stealthstylz
Club Retro Rides Member
Posts: 14,812
Club RR Member Number: 174
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Reusing Valve Train Partsstealthstylz
@stealthstylz
Club Retro Rides Member 174
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As much as I think it's a good idea, I'm not going to fit inserts. The Timeserts are incredibly expensive, more than a complete used engine! And I don't have the facilities to remove the block to fit them, even if I use a cheaper version. It'd be worth ringing local engine/engineering places see if somebody will come out and fit them for you. I've built ~30 Rover V8s and every one that has been overheated has needed them.
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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Can they be done with the block in the car?
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stealthstylz
Club Retro Rides Member
Posts: 14,812
Club RR Member Number: 174
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Reusing Valve Train Partsstealthstylz
@stealthstylz
Club Retro Rides Member 174
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As long as there's access to get in with a ratchet or tapping handle yeah. Just tape up the water jacket and other holes etc so swarf can't get in anywhere.
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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Ok, I had an investigation and if I can use the old heads as a drill guide or make one from thick angle, I may have a go.
Unfortunately, top German equipment is out of my price range, so a V Coil insert it'll have to be!
However, I'm still tempted to gamble the head gasket set and stretch bolts (£65) on the block threads being OK?
Opinions please?
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I don't think the bolts are stretch bolts, I have always re-used the old ones.
I used helicoils (1.5 diameter long) in the one I repaired, worked fine.
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Last Edit: Oct 5, 2022 19:03:48 GMT by kevins
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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Tin gaskets are normal, composite gaskets are stretch.
What was the problem and how many inserts did you use and was the block in a car?
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I used the std bolts with the composite gaskets (done up to the std spec for them), has worked fine for 10 years, I think the engine had been overheated, when I tighted the bolts 2 stripped in the block, I used helicoils which were 1.5 x the bolt diameter long.
They were drilled and taped in the car (TR7V8) but one did end up a bit off and was a tight fit to get back in. Using the old heads as a drill guide seems like good idea.
This was in the first engine I had, it had a persistant knock from the bottom end when hot, investigations found a twisted con rod as well but even with this and the offending piston replaced it still knocked, I tried all sorts of things but in the end fitted a secondhand block and pistons which fixed it (I think the liner may have been moving), this doesen't have any helicoils but has been fine with the std bolts and composite gaskets for at least 10 years now.
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Last Edit: Oct 5, 2022 20:41:01 GMT by kevins
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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Live and learn, took the advice on the internet from RPI and others! Brought them now, so will use them. Think I'm going to fit heli's, still can't afford the Wurth version though!
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stealthstylz
Club Retro Rides Member
Posts: 14,812
Club RR Member Number: 174
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Reusing Valve Train Partsstealthstylz
@stealthstylz
Club Retro Rides Member 174
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Anything is better than the stock threads lol. Just had a look at the timeserts - forgot how expensive they are as to me they're "free" lol. Helicoils will be fine.
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andyborris
Posted a lot
Freedom is just another word for nothing left to lose.
Posts: 2,145
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I'm retired now, all my "free" has stopped!
Anyway, one head is off and (worryingly) the head gasket looks perfect. It's a tin gasket and is without damage, even the crush ring round the cylinder looks even.
The chap who I brought the car off said the engine had been stripped, checked before the conversion, certainly looks like it has had all new gaskets.
Can't see any damage to the head or the block, so it's either the other bank or I've got a bigger problem.
I'm hoping, that if I use a right angle drill chuck, I'll be able to fit the coils in every bolt hole....
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stealthstylz
Club Retro Rides Member
Posts: 14,812
Club RR Member Number: 174
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Reusing Valve Train Partsstealthstylz
@stealthstylz
Club Retro Rides Member 174
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The only other issue that causes headgasket type issues is the liners, everybody states for a fact that the 3.5/3.9 don't suffer from it but I've seen a couple that have. Either that or the block deck face is wobblier than a fat man on a pushbike.
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You have put a straight edge along and across the heads obviously? And the block face? The later engines suffered from liner slip/porosity, but stealthstylz will be able to tell you more about that than I can
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