Esprit Turbo project car - part3 - the further continuation

[Lotusfab]

Oh dear, I've really done it this time!

[Lotusfab]

Did any one spot my mistake? I wrote the valve clearances in 100 ths not 1000ths. They need another zero. Well I'm glade I have taken it apart. The head weld has been poorly done, but it's not in a critical place. It looks like they broke it removing a carrier bolt. It's just the bolt area that's been welded. They have good penetration but have nit tidied it up very well! The tensioner is new, oil pump is refurbed, water pump is not leaking but was poorly put on. The head gasket looks new. It has been rebuilt. Still need to measure all tolerances. Water pump is going for a refurb. I havn't decided whether to replace the head with a recon one. My engineering head says the weld is fine but not very neat.heres some pics of the weld, what do you Chaps think?

It's  only the top edge of the cylinder head where the bolt thread goes. Looks like they couldn't  get the bolt out and snapped the casting! 

[Lotusfab]

Note the tiny green dots on the cam pulleys. These are the timing marks. Uk Turbos have green dot pulleys unless you wish to save the planet then you go blue and loose 10 HP! No Chance! 

I'm not detuning Mr Bonds ride!

[Lotusfab]

It's got the correct pistons! All looks pretty reasonable just have to check the bearings etc.

[JerryS]

Hi Fabian, looking at the length of the weld repair I wonder if the head had been dropped on the stud snapping off that chunk of the carrier face. Considering how tricky these repairs can be I think it looks quite solid. The outside bead looks quite neat really.

[eeyoreish]

This all makes me feel better about how many pieces my engine has been in for the past few weeks. At least mine is still in the car!

[Lotusfab]

Hi Jerry, 

thanks for the input. Yep I think you might be correct, someone dropped it! Shame really as it looked in good shape otherwise. I think they could have tidied up the weld much better although some engineers really don't care what things look like! 

[Lotusfab]

You can see the inside of the weld in the above picture of the head on the bench. The weld is above the valve. It seems obvious to me now,someone dropped it on the stud. I'm thinking tidy up the outside and use it, once I have checked the valves and guides for wear. To be honest you can't see it unless the engine is on a stand! 

[JerryS]

Yes maybe think twice about tidying the weld - would be a shame to remove metal risking opening up a possible channel for oil to seep through but I do understand maintaining the standards you've set for your rebuild. It's not that noticeable buried where it is.

[drdoom]

5 hours ago, JerryS said:

Yes maybe think twice about tidying the weld - would be a shame to remove metal risking opening up a possible channel for oil to seep through but I do understand maintaining the standards you've set for your rebuild. It's not that noticeable buried where it is.

Agreed !!

[Lotusfab]

Well I have had more time to think about the head and Jeremy on hear has inspected it. The weld is not in a critical area and the crack on the edge in the stud area caused by dropping the head on the stud. Whilst the weld is functional I think it should be possible to do this repair to a much higher standard wherevit almost invisible. I will be taking the heals to an engineering shop I know and get them to redo the repair or dress it correctly. The owner always tells me the repair will be as strong as the original. If he's not happy with it  I will replace the head. 

The main block has now been extensively cleaned and painted. All of the seals and bearings have already been replaced. The bores and pistons are very good showing little wear.. I still have to remove all of the valves and check these for wear. 

Ive started to look into sealants as I reassemble. At the moment I am planning on...

Permabond 136 for the sump, gearbox covers.

Wellseal for both sides of paper gaskets.

oil pump gasket dry fit.

If anyone has any better ideas I would like to hear them  before I reassemble. 

[NR2k]

@lotusfab

Have you seen this image before?

From this listing on ebay. 1982 copy of lotus world.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F303028768263

[Lotusfab]

Hi Nicola,

no havn't seen that before, excellent picture!

Trim

well have just returned from Norfolk with the door cards and header as done buy Steve at Fulcher coach works. Superb job, will post some pics tomorrow. The seats are almost complete, they will be stunning. He had an old Turbo seat and the leather colour matched mine exactly, Lotus Gold! 

The rear seat panels have been remade with new hardboard and are Vinyl covered. The collars have also been remade with new leather and foam. All of the seat will be Rouched as per the original. Amazing work and attention to detail. The original seat backs were well past their best as was the rest of the seat. It makes such a difference with new leather and stitching. The Effect as Lotus intended. 

[Steve V8]

On 13/01/2019 at 21:10, Lotusfab said:

Ive started to look into sealants as I reassemble.

I find clear silicone is the best for looking into... 

[Lotusfab]

Turbo camshaft identification. 777 stamped on it, as in picture.

[Lotusfab]

Cylinder head

Not being very happy with the repair I'm off to see Cranford engineering, Leatherhead. They specialise in aluminium welding and just about everything else. They sorted my gear lever which is now the ultimate upgrade. The thin levers snap where the spiro pin is located. I got Cranford to weld a thin lever to a thicker base lever. They did it so well I couldn't see where it was welded  or joined. Now I have the best solution. A elegant thin gear lever on top and the better engineered bottom. It's been away for chroming. 

 Personally I think the head repair is pretty poor done by someone without major engineering equipment or milling machines. So it's off to Cranford to get their expert advice. I'm hoping they will be able to make a good as new invisible repair. If it's not possible a new head from PNM. 

Im sending Pete at PNM my water pump for a recondition, I'm not taking chances with somethiing that's a 15 minute job now or days of struggling when it's back on the car. 

Will report back on my Cylinder head tales of woe!

[Lotusfab]

[Lotusfab]

Calendar head

cranford engineering have inpsected the weld. They say it’s well done and there is no issue with tidying it up. So I have left the head with them. When it returns all the valves have to be removed to check the seat condition, wear and guide wear. I have dial gauges  but need to add quite a few tools to my list. 

I have stripped the cam holders. The followers need measuring for wear and their holes. The end float on the camshaft is suspicious so will have to measure it as well and change the selective thrust washer and seals if required. 

I have decided to measure the bores and pistons for wear. Quite cost effective to replace them now if required as it’s all apart. 

Essentially a full rebuild so this might take me some weeks.

[Lotusfab]

Paul at Cranford has worked his magic. I could find the weld! Here it is!

[CHANGES]

I take it you will put the stud in the correct place when you put it back together..  

I think its a good job you are taking the time to rebuild the engine considering everything else you have done, especially when you disassembly shows such poor shimming and parts fitted incorrect..  This would put a question mark on the overall build standard. Also considering how long it has stood with unknown assembly compound you could have struggled to get oil pressure without a pre prime and damaged other surfaces in the process.  

May also be worth going the extra mile and addressing some of the inherent deficiencies , ie port alignment and balance etc while you are at it..     

[Lotusfab]

Thanks. Yep I need to go through all if this very carefully. This is how it came off. . I have just removed the front crankshaft sprocket and casing, the sealant used was RTV, probably not appropriate for this application. I would have used Wellseal. 

I'm just ordering a lot of measuring equipment to check every component. Shame to have to damage all the new gaskets, but a necessary evil. I need to check the valve seats and guides. There's also a lot of shims to order. 

Water pump is just going off to Pete at PNM. For a recon. It was done before, but I dontbikenthe feel of it. 

[Lotusfab]

18 minutes ago, CHANGES said:

I take it you will put the stud in the correct place when you put it back together..  

I think its a good job you are taking the time to rebuild the engine considering everything else you have done, especially when you disassembly shows such poor shimming and parts fitted incorrect..  This would put a question mark on the overall build standard. Also considering how long it has stood with unknown assembly compound you could have struggled to get oil pressure without a pre prime and damaged other surfaces in the process.  

May also be worth going the extra mile and addressing some of the inherent deficiencies , ie port alignment and balance etc while you are at it..     

Presumably all the studs are incorrect? They should be on the outer corners so you can get the nuts on easily? The parts manual isn't clear as it only shows one. Thanks for pointing this out. Please let me know if you spot anything else. Incidentally what sealant do you use for the core plugs? I'm not a fan of Wellseal. 

[CHANGES]

position studs as pic

On core plugs I use loctite  572 ..

[Lotusfab]

Thanks Dave, you set the standard in that pic! 

Was that head Aqua blasted? 

[Lotusfab]

Well  that does it I'm stripping the head completely and aqua blasing after Inhave checked the valve guide tolerances and seats.

There's lot of measuring kit on the way!