1397 piston and liner kit
- Thread starter potentz
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I was told by our Renault Training man (Nick Erasmus) that they were prone to break rings if they were revved too hard while cold. I have seen motors last +200K miles before rings are just worn out. 2.5mm ring gap, 0.3 -0.4 when new. Valves with concave seats, and timing chains with no more adjustment. Bottom ends were amazing, if regular oil changes, but oil pumps were starting to give lower pressure.
These motors with regular servicing were amazing.
Long live the wedge head !!!!
Ray
PS, When I started seeing "807" motors, I was out of the workshop, and so only worked with second hand motors that came out of scrapped cars. Mixed conditions !!! But parts were cheap to rebuild, never a part job, and they would give +200K Km without problems, and some were treated real hard.
These motors with regular servicing were amazing.
Long live the wedge head !!!!
Ray
PS, When I started seeing "807" motors, I was out of the workshop, and so only worked with second hand motors that came out of scrapped cars. Mixed conditions !!! But parts were cheap to rebuild, never a part job, and they would give +200K Km without problems, and some were treated real hard.
My Renault guy is in awkward circumstances at the moment & not able to devote time to a major job.
The R8 had a radiator hose connector rupture & did a swift coolant dump. (I was in traffic and not watching gauges as much as traffic at the time & it had happened when next I glanced at the gauges - my fault then).
We replaced the head with a 1289 one & some combustion chamber relieving (ended up at 9.8:1 cr) but the bores looked 0K. It drove seemingly normally except for idling roughly & missing on a very low & steady throttle opening (as in cruising). Our first hypothesis was muck in the DC0E but it turned out to be 3 cylinders on 120+ & one on 80+ psi.
I'm getting a full kit from Ian but, given my mechanic's circumstances, just doing one cylinder for now might be the path to getting it quickly back on the road. (Having had it off the road being fettled for 12 months, I'm keen to have it back.) It'll be my mechanic's call as to what he'll be in a position to manage.
The motor was second hand when fitted & used to have 44kw at the wheels but is now 4Okw with 3 & 3/4 cylinders. I certainly don't rev it out until warm. As Ray says, I think them to be nice motors which have responded well to the mild reworking that the R8 & Djet have had.
cheers! Peter
The R8 had a radiator hose connector rupture & did a swift coolant dump. (I was in traffic and not watching gauges as much as traffic at the time & it had happened when next I glanced at the gauges - my fault then).
We replaced the head with a 1289 one & some combustion chamber relieving (ended up at 9.8:1 cr) but the bores looked 0K. It drove seemingly normally except for idling roughly & missing on a very low & steady throttle opening (as in cruising). Our first hypothesis was muck in the DC0E but it turned out to be 3 cylinders on 120+ & one on 80+ psi.
I'm getting a full kit from Ian but, given my mechanic's circumstances, just doing one cylinder for now might be the path to getting it quickly back on the road. (Having had it off the road being fettled for 12 months, I'm keen to have it back.) It'll be my mechanic's call as to what he'll be in a position to manage.
The motor was second hand when fitted & used to have 44kw at the wheels but is now 4Okw with 3 & 3/4 cylinders. I certainly don't rev it out until warm. As Ray says, I think them to be nice motors which have responded well to the mild reworking that the R8 & Djet have had.
cheers! Peter
I emailed him a few weeks ago, asking after the progress on the 4CV (I think) and yes, "awkward" isn't a bad word judging from his reply. I do hope things improve for him.
You have reminded me, re your R8 mishap, that I must double check the warning light switch bolted to the head before heading east in April. Sorry about your engine, but thanks for the reminder. I've never had a Renault hose fail. I guess I've replaced the odd one if at all dubious during some other job, but they've typically been good for decades, the French ones at least.
Apologies for the slight hijack.....
I did once rebuild an R10 engine with broken rings, forced up past the top of the piston and making square dents on the head, from memory at 120,000 miles+. And, I recall thinking that perhaps it also happened at the age where they've been neglected too ("car isn't worth spending money on so I'll just top up the oil...").
It wasn't a hose as such John. It was one of those little plastic T pieces with the brass bleeder vent wheel in them (part of an R12 heater hose circuit). The plastic ruptured. We have done a very careful re-alignment of hoses with the replacement so that there is no lateral tension on it at all.
It is my R8 that he was working on but I think that you have in mind an elaborate 4CV restoration be was part of. That (1953) 4CV is currently in the National Automobile Museum of Tasmania in Launceston. It's "restored" to better than factory-fresh condition (apart from needing new axle tubes & trunnion bearings - no doubt someone out there has some).
cheers! Peter
It is my R8 that he was working on but I think that you have in mind an elaborate 4CV restoration be was part of. That (1953) 4CV is currently in the National Automobile Museum of Tasmania in Launceston. It's "restored" to better than factory-fresh condition (apart from needing new axle tubes & trunnion bearings - no doubt someone out there has some).
cheers! Peter
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Ah, bad luck. My 4CV trunnion bearings are bronze, machined to a light press fit on the pins and rotating in the (extremely) hard steel caps and lubricated with Molygrease - no play after 20+ years.
Sounds good. I shall pass the advice cum suggestion on.
I assume that one can remove a piston & attached con-rod up through the sleeve. (I ask in case the big end diameter in the 1.4 motor is too large for this - I seem to recall an awkwardness with the 1.4.)
cheers! Peter
cheers! Peter
As you are buying a full set of pistons and sleeves, take yours out as a unit with the piston in the liner, get the new pistons fitted to your old conrods by a machine shop, and fit them to your liners and fit them to the block. It might be worth getting your bigends checked for roundness/size. It doesn't seem to me to be an economical move to replace one piston and liner, when you have a set.
With a 77mm bore in the 807 (R16TS) the conrod will not fit up through the liner, but I would only be guessing on a 1.4.
Our first hypothesis was muck in the DC0E but it turned out to be 3 cylinders on 120+ & one on 80+ psi.
With a standard cam and close to 10 to 1 I would have expected the comp pressure to be greater, around 160+PSI. I remember testing standard 1.4s back in the day, to often have them testing 150, but maybe carbon content of the chambers was greater then with lesser oils and fuels. My warm R16TS motor comes in at 210 PSI with a cam with quite a bit of overlap.
With a 77mm bore in the 807 (R16TS) the conrod will not fit up through the liner, but I would only be guessing on a 1.4.
Our first hypothesis was muck in the DC0E but it turned out to be 3 cylinders on 120+ & one on 80+ psi.
With a standard cam and close to 10 to 1 I would have expected the comp pressure to be greater, around 160+PSI. I remember testing standard 1.4s back in the day, to often have them testing 150, but maybe carbon content of the chambers was greater then with lesser oils and fuels. My warm R16TS motor comes in at 210 PSI with a cam with quite a bit of overlap.
I seem to recall the 1289 con rod will fit through the bore but the 1397 will not as Renault moved to a larger diameter big end just to make life difficult.
Thanks for that Alan but, as noted in post #43, there are other motivations in play. Mind you, if Graham is right then the "slip in one piston" option will lose its attraction. (The cam isn't standard as it happens but one supplied by Collier's to a "fast road" brief.)
Our other option for now might be to slip in a second hand 1.4 I have.
cheers! Peter
Hello Ian T,
What are the chances you still have one set of 1397 pistons and liners?
Or anybody else??
Thanks in advance with fingers crossed!
Bruce.
What are the chances you still have one set of 1397 pistons and liners?
Or anybody else??
Thanks in advance with fingers crossed!
Bruce.
4CVG. Is this the car you will bring to Griffith at Easter?
More carefully: this is the car that I plan to bring to Griffith at Easter.
cheers! Peter
With my experience with the 1.4 engines here in Canada the mains bearings are the same size as the 807 motors but the connecting rods are still the same bearings as the 810 /688 / 812 motors ! The connecting rods in the 1.4 motors are built as heavy as the 812 motors minus the brass inserts on the connecting rod end and the 2mmm shaved off which allows them to float and for the 1108 crank spacing because it uses the short stroke offset G crank.
Not sure if this is helpful but from what I remember the rod does fit up thru the liner of the 1.4 motors .
Manic gt
I think I've got some sets of new 1.4 b/ends and mains - do you need std?
I don't yet know as the engine is still in the car. My memory is that the journals are pretty good quality hardness in these engines so my guess is that they won't have to be ground & std. would be fine.
I imagine that I'll be availing myself of your offer but I won't see my mechanic until tomorrow to ask his advice.
(The trouble with rebuilding one of these when an old fart is that one might well die before it is properly run in - grrr!!.)
cheers! Peter
Regular oil changes = good crankshaft. I've had 60 psi oil pressure since 1974. Same crankshaft. Last measured on spec in 1988.