tomcat59alan
Well-Known Member
What's the problem, if you can do a single cylinder engine you can do a V8, just more bits to lose.
What's the problem, if you can do a single cylinder engine you can do a V8, just more bits to lose.
Talking of which, one piston down and ...?
Still fighting with the next....
Replacement Con Rods have arrived.....looking sexy, test fitted to original pistons, perfect. Gudgeon Pins have been measured as have the piston pin holes, and after a quick clean with a bit of Scotch Brite to get the oxidation off, they are a beautiful fit with velvet smooth-ness....you know that silky machine fit...!!!
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ovalandrover
Well-Known Member
jamesmartin
Well-Known Member
you can get them cheaper, but i would have done with a rebore£240.00 a set maybe the stumbling block.
tomcat59alan
Well-Known Member
I hope you have weighed them, don't want it running uneven.
I just gave Rimmers price James. Suppose you could get them from an engine shop. But the days are long gone around here when you could go into Hepolite House on Brook St and get them or loose single rings over the counter. And they WHOULD be in stock unlike today were you get stuff a week on Thursday.
.tomcat59alan
Well-Known Member
To true Tony, I had to get high comp pistons from Israel for the E type, all that was available in this country was low comp.I just gave Rimmers price James. Suppose you could get them from an engine shop. But the days are long gone around here when you could go into Hepolite House on Brook St and get them or loose single rings over the counter. And they WHOULD be in stock unlike today were you get stuff a week on Thursday.
Well after a week or so of fighting with the pistons I can grandly announce I have completed 2 and a half of them!!! I have soaked them in Paraffin, Diesel, Hypersolv, Pure Vinegar....I even boiled them in pure vinegar too...that really stinks....
2 are now with out rings and half of one is just left with the top compression ring......and then it all went pear-shaped.
I was working on four pistons at a time....
When I was trying to get the ring to budge on one of them when the pin sized punch I was using snapped, slipped and dinked the edge of the groove to leave a nice little dent in it!!.....uuuuurrrgggghhhhhhh
OK, put that one to the side and start to work on another one fresh from the pan.....got the top compression ring out and the oil rings, and as I was picking out the last fragment of the second compression ring......ping.....the land snapped off.....OH FECK....
I had only managed to get this many rings out by this time....
Gutted, absolutly gutted.....I apologised to Adam and we discussed what the next sep would be...either new pistons or S/H pistons.....we will discuss this again later....
In the mean time I have measured the bores, our Lead Hydraulic Engineer measured them and the results suggest the bores have had very little wear......they are all measuring up at 3.4975 to 3.4980" and one at 3.4990"....we used a Moore & Wright set of gauges & his UKAS calibrated bore gauges too...so we are fairly certain they are only 26k old!!
Tonight I turn to the heads....but these are seized solid too.....joy!
2 are now with out rings and half of one is just left with the top compression ring......and then it all went pear-shaped.
I was working on four pistons at a time....
When I was trying to get the ring to budge on one of them when the pin sized punch I was using snapped, slipped and dinked the edge of the groove to leave a nice little dent in it!!.....uuuuurrrgggghhhhhhh
OK, put that one to the side and start to work on another one fresh from the pan.....got the top compression ring out and the oil rings, and as I was picking out the last fragment of the second compression ring......ping.....the land snapped off.....OH FECK....
I had only managed to get this many rings out by this time....
Gutted, absolutly gutted.....I apologised to Adam and we discussed what the next sep would be...either new pistons or S/H pistons.....we will discuss this again later....
In the mean time I have measured the bores, our Lead Hydraulic Engineer measured them and the results suggest the bores have had very little wear......they are all measuring up at 3.4975 to 3.4980" and one at 3.4990"....we used a Moore & Wright set of gauges & his UKAS calibrated bore gauges too...so we are fairly certain they are only 26k old!!
Tonight I turn to the heads....but these are seized solid too.....joy!
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jamesmartin
Well-Known Member
depends on piston size ,but generally a fore aft measurement compared to side to side measurement at top of swept area gives you the wear,bore surface condition is vital in my experience water marks tend to smoke and honeing needs some depth, unless you buy pistons in sets size can vary by quite a few thou, high compression pistons are imo a better choice
The bore was measured in 3 axis within the top 20mm of the bore....all readings the same....and our LHE builds, re-builds and re-bores Aircraft jacks capable of 200+ Tonnes under test.....pressures inside are measured in the 10's of thousand PSI, so his bore measuring skills I would match against anyones!
So it is possible to use higher compression pistons in the engine with little detrimental effect??
I am always keen to learn from the more learned...
So it is possible to use higher compression pistons in the engine with little detrimental effect??
I am always keen to learn from the more learned...
jamesmartin
Well-Known Member
im not doubting anyones skills in measuring but where they are taken matters, very top of swept area at 90 degrees to crank is the greatest wear area, i usually fit h/c pistons (9.35)in replacement of l/c (8.13) unless insisted not to
While Adam is checking out Pistons/engines/etc I turn my attention to the heads....
If you remember when we took them off they were not looking the best...
So working on the left hand bank first, I took the PAS pump off the front and placed aside.
Looking at the inside of the rocker space, it isn't looking to bad at all. This engine was looked after, before it was laid up with no spark plugs in the holes to prevent the bores from seizing up...
Time to get the valves out, first one is an exhaust valve.
Place the spring compressor on the valve base and the spring cap and compress sufficiently to get the collets out.
Using a magnetic tipped tool, it makes it easier to get the collets out
Umcompress the spring
And remove the spring and cap
Push the valve out
The valves slide out nicely with a smooth velvety machine feel to it, no jerking, roughness or sticky points.....the stems look in good condition, pity the base and the edges are little mucky!!
With luck and some patience, these *may* clean up
The seats at the moment look mucky, hopefully with a clean up we can see if they are beyond hope!
The next valve (intake)
Place the valves in order they are removed....I used tubs marked L1...L2...L3 etc for Left Bank 1st cylinder etc..
Once all the valves have been removed, all of which came out nicely, another testiment to a looked after 26k miler, it heads over to the parts cleaner for a quick scrub down.
Compared the two heads as a before and after.....
Valve seat, whilst grubby aren't pitted, damaged or scored....maybe after a bit of lapping, they will polish up....only giving it a try will tell, nowt to lose trying....
Remember it did look like this....
Next is to do the same to the Right Bank head and see if that clean ups OK....but this is the one where 2 valves are actually stuck open, so maybe this one will present more of a challenge to clean up!
After that is done, time to asses the condition of the guides etc.....
Just waiting on news from Adam re: Piston situation.
If you remember when we took them off they were not looking the best...
So working on the left hand bank first, I took the PAS pump off the front and placed aside.
Looking at the inside of the rocker space, it isn't looking to bad at all. This engine was looked after, before it was laid up with no spark plugs in the holes to prevent the bores from seizing up...
Time to get the valves out, first one is an exhaust valve.
Place the spring compressor on the valve base and the spring cap and compress sufficiently to get the collets out.
Using a magnetic tipped tool, it makes it easier to get the collets out
Umcompress the spring
And remove the spring and cap
Push the valve out
The valves slide out nicely with a smooth velvety machine feel to it, no jerking, roughness or sticky points.....the stems look in good condition, pity the base and the edges are little mucky!!
With luck and some patience, these *may* clean up
The seats at the moment look mucky, hopefully with a clean up we can see if they are beyond hope!
The next valve (intake)
Place the valves in order they are removed....I used tubs marked L1...L2...L3 etc for Left Bank 1st cylinder etc..
Once all the valves have been removed, all of which came out nicely, another testiment to a looked after 26k miler, it heads over to the parts cleaner for a quick scrub down.
Compared the two heads as a before and after.....
Valve seat, whilst grubby aren't pitted, damaged or scored....maybe after a bit of lapping, they will polish up....only giving it a try will tell, nowt to lose trying....
Remember it did look like this....
Next is to do the same to the Right Bank head and see if that clean ups OK....but this is the one where 2 valves are actually stuck open, so maybe this one will present more of a challenge to clean up!
After that is done, time to asses the condition of the guides etc.....
Just waiting on news from Adam re: Piston situation.
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ukadamwest
Well-Known Member
I may have sourced a set of pistons..
So with the options of being 8.13:1 or 9.35:1 compression ratio.
So with the options of being 8.13:1 or 9.35:1 compression ratio.
8.13 -1 is what you have now, 9.35 - 1 will be flat tops.
