Ian's S4s refurb

[Chillidoggy]

Slight setback. Four sheared bolts in the pump cover, and they’re resisting my best efforts thus far. The chances are they’ve corroded in the cover and expanded. Either that or some kind soul has threadlocked them. I’ve got some other plans for removal in the pipeline, but bitter cold round these parts is stopping me venturing outside for the moment.

[Sparky]

Bitter cold?  Ya big girl's blouse.  I've done 2 Esprit cambelts, outside, since yesterday.

That said, bit of a shocker on the housing.  Don't think I've seen one that bad, even on Christine.

[Chillidoggy]

39 minutes ago, Sparky said:

 

That said, bit of a shocker on the housing.  Don't think I've seen one that bad, even on Christine.

It’s not fully stripped yet, so there’s potential for more!

Took the cylinder head in to Connaught Competition Engines this afternoon. I had originally just planned on new valve guides and seats recut, but I’ve a feeling it’s unlikely to stop there. While we were there, we popped one of the exhaust valves out. Under the magnifying glass, etched on it was the Lotus P/N B910E1383F. I am assuming that this is one of the original sodium-filled valves as I have no evidence to say the engine has been stripped previously, but to be confirmed.

[Gjk]

Can you not take the engine indoors?   

 

had these put in on back of house so I “could” fit the car in...   obviously I have not asked the boss yet!

 

[Gjk]

Sorry! Didn’t mean to bomb this thread 😳

[Lotusfab]

4 hours ago, Chillidoggy said:

It’s not fully stripped yet, so there’s potential for more!

Took the cylinder head in to Connaught Competition Engines this afternoon. I had originally just planned on new valve guides and seats recut, but I’ve a feeling it’s unlikely to stop there. While we were there, we popped one of the exhaust valves out. Under the magnifying glass, etched on it was the Lotus P/N B910E1383F. I am assuming that this is one of the original sodium-filled valves as I have no evidence to say the engine has been stripped previously, but to be confirmed.

Im just javingbthe cylinder head done again! Sodium valves are all worn 1.5 thou differential on the stem. Only option is solid valves which will make it run hotter, or used valves. Guides are also worn on the exhaust side. Big bill coming my way! Your burn looks similiarmto what I had. The inlet guides are cast iton. The new ones are bronze.you can have an oil seal now, but as the Lotus engine runs on its side I dont think they are necessary. 

[Giniw]

6 hours ago, Sparky said:

I've done 2 Esprit cambelts, outside, since yesterday.

How did you adjust the belts tension? Aren't they supposed to be tensioned at 110Hz with an ambient temperature of 15-25°C? (IIRC, I don't have the specs here with me!)

5 hours ago, Chillidoggy said:

I am assuming that this is one of the original sodium-filled valves

Are there after market ones? I hope the original are still available?

[Giniw]

1 hour ago, Lotusfab said:

Only option is solid valves

Shucks 😕

EDIT:  I just had a quick look and it seems the  can still be bought? (SJS)

Edited February 8, 2020 by Giniw

[Lotusfab]

Ahhh, thanks. Not sure if they are solid or used?

Apparently they solid valves are of no concern heatwise, unless you plan to race.

[Giniw]

I don't think SJS sells used parts. As for being solid or sodium filled, I would say I expect them to be sodium filled from the part number but I could be wrong. Better ask them to be sure!

[Chillidoggy]

Frankly, I don’t care whether the exhaust valves are filled with sodium, custard, or the wife’s shampoo. I’m not passing comment on any others, but as far as my own cylinder head is concerned, it’s in the best professional hands, and I’m leaving to those who have a proven track record and know exactly what they’re doing.

As for the weather, well it’s a bit warmer today, so I might be able to make up some lost ground in the degreasing. Well, apart from the bloody rain, that is.

[Gjk]

Are you going to re-apply the wrinkle finish to the cc and plenum or powder coat?

[Chillidoggy]

1 hour ago, Gjk said:

Are you going to re-apply the wrinkle finish to the cc and plenum or powder coat?

The wife is on standby for that job as soon as the paint stripper and paint arrives.

[Gjk]

Hopefully the weather will pick up or can you slyly put it in the oven?

[Chillidoggy]

The weather did indeed brighten up, and I managed to degrease the cam housings, sump, and sump baffle. I then progressed to strip the remainder of the engine, which went smoothly. The only things left are the liners, and those things are in there pretty solidly, so I’m going to have to manufacture some kind of puller to break the seal.

Considering the high performance nature of the engine, and 75,000 miles, I have to say it’s in remarkably good condition. I would estimate that it had another 20 - 30,000 miles in the bottom end before it really would need a rebuild. I’ve rebuilt engines with less mileage on them and they’ve not been anything like as good. As I said before, as far as I know it’s the original engine, and has never been apart before, and if so, it’s a tribute to Lotus. The cylinder head is a different matter however, but I could have just refinished it, and had done with it,

So, I reckon the original Mahle forged pistons will go again with new rings, the crank has almost no markings on it, and apart from one bearing shell which is showing copper, the remainder are still grey. So, a light polish and that can go back in with standard bearings. The Nikasil liners still have some of the original honing pattern too, but I shall probably be replacing them with ductile iron liners.

The remaining degreasing will have to wait until there’s another weather window, hopefully Monday, because by all reports it’s going to be a tad windy tomorrow and I’m supposed to be taking my old mum out for her birthday. That’ll be fun.

[Gjk]

Was it a big end bearing shell or a main bearing shell that showed the signs of copper?

also, what colour was the oil when you drained the engine?

[Hornsey Boy]

8 hours ago, Chillidoggy said:

The wife is on standby for that job as soon as the paint stripper and paint arrives.

Hi Ian @Chillidoggy  I am looking to repaint the red bits on my engine, what brand/colour code of paint are you going to use ?

Dragan

[CHANGES]

12 hours ago, Gjk said:

Was it a big end bearing shell or a main bearing shell that showed the signs of copper?

If it goes to the normal ware format on these engines it will have been number one main bearing top half.. 

I am sure Ian will confirm one way or another in time..   

[Chillidoggy]

Yes, it’s the usual suspect. All that load from the accessory drives has to go somewhere, eh?

Dragan @Hornsey Boy- I’m going to use VHT Wrinkle Plus red.

[jonwat]

20 hours ago, Chillidoggy said:

The only things left are the liners, and those things are in there pretty solidly, so I’m going to have to manufacture some kind of puller to break the seal.

There's a guy on the Elite/Eclat/Excel forum who made one & was happy to loan it out, maybe worth asking over there. 😀

[Chillidoggy]

Thanks Jon, I'll bear that in mind. I'm trying to solve the problem another way first but we'll see.

Meanwhile, as it was like a wind tunnel outside, I took the crank up to Connaught Competition Engines this afternoon for a measure up, and if it looks to be within spec, a polish. I've caved in and told them to skim the head, and so stump up for the Vernier sprockets to time the cams properly. I've also spoken to Garry Kemp, taken his advice regards cylinder liners, and I'll be ordering up the required parts from him once I know what the crank is like.

[Gjk]

Hi Ian I was just trawling through the SE service notes and found this snippet. Is there a similar head gasket variation available for the S4s?...   just a thought...

cheers 

grahame

[CHANGES]

 

1 hour ago, Gjk said:

Hi Ian I was just trawling through the SE service notes and found this snippet. Is there a similar head gasket variation available for the S4s?...   just a thought...

cheers 

grahame

That all went out of date with Noah and his arc..  The replacement Goetze gasket was supposed to be in line with the thicker gasket..    Not sure which one as there were originally 2 thicker than the original ..      Because of the age of theses engines it is never certain how many times the head has be skimmed ..  Always best to do an assessment measurement  by using the cam timing with True TDC and DTI with dial gauge..     This will allow you to work out how much if any can be skimmed to maintain cam timing or improve it..    The easiest way to get cam timing spot on after skimming is to use vernier pulley's , that way you can skim to what ever you need to clean head ..  If it needs a lot you can cut back the valve seats to correct the compression ratio..    It all very doable  its just knowing what to do, how much you can get away with  and having the tools ..     

[snowrx]

5 hours ago, Gjk said:

 Is there a similar head gasket variation available for the S4s?...   just a thought...

 I found the Goetze to be the thickest of the three gaskets I've sampled.

 

 

[CHANGES]

There is a  head gasket Gary Kemp supplies that is circa .020'' thinner than the Goetze gasket.  This is more in line with the original preferred first build gasket thickness..