TR4/4A Calling All TR4A's

[RJS]

Hi All,

Looking to confirm some info on the proper PCV configuration. Mine is a 1966 with the Smith's pancake PCV number FVP 2001/02 (with the domed lid, not the flat lid). If you have one installed which is functioning properly would you be able to open it up and tell me what you find inside?

What I am hoping to confirm is that the inside includes only the rubber diaphragm and the spring but, not the little metal pintle/poppet.

My car ran perfectly for years with the PCV in place with no oil leaks. Then mysteriously it started leaking oil like crazy due to crankcase pressurization. I tried everything, including inspecting, checking, servicing and cleaning the PCV which included the diaphragm, spring and poppet. No help.

Then today, low and behold I was looking through the Bentley Official Workshop Manual and in Fig 26 on p. 145 it shows a diagram of the PCV for the '66 TR4A with the diaphragm and spring but, NO poppet! Per the manual, it is clearly NOT a part of the system.

I have suspicion that my mechanic incorrectly put the poppet in there last time he serviced the car/PCV - thinking he was doing me a favor. It is true later versions of this PCV had the poppet in place (i.e. as used on the TR250 and early TR6) but, I am pretty confident the TR4A did not and just looking for confirmation.

Thanks all for reading my long note. Looking forward to hearing back.

Bob

 

[HerronScott]

Bob,

I would be more than happy to check the one out in mine when I can get to it this weekend to see what it has.

Scott

 

[RJS]

Scott,

That would be huge and much appreciated. I have been trying to track this issue down unsuccessfully for about 18 months and driving me insane since everything else checks out perfect (compression, etc.).

Bob

 

[CinneaghTR]

My car did not come with one (surprise!) and the one I sourced from TSI did not have the poppet, just the diaphragm and spring.

Good luck!

 

[3798j]

Bob, This probably won't help you, but my '66 has the flat top (FVP2003/11) with diaphram, spring, and pintle. If you'
re convinced it should'nt be there, why not remove it and see if there's an improvement?

 

[RJS]

Jeremy,

Thanks. Now I really feel like I am getting somewhere! I can't tell you how happy I will be if this whole issue is solved this easily.

Any other TR4A owners able to weigh-in on this topic?

Cheers

Bob

 

[RJS]

Jay,

Much appreciated. I guess I'll wait and see what other owners who have the domed PCV like mine (FVP 2001/02) report. In the meantime, I plan to do exactly as you say this weekend - remove the pintle from the guts of the PCV and run a test.

Bob

 

[LBCs_since_1988]

I've got a '66 and mine is the 'flat-top' style which I truly believe is original to the car.

 

[sail]

My 66 came with a flat top from at least 20 years ago. I took it off and added a filter on the valve cover and a breather pipe on the crankcase.

 

[HerronScott]

Well Bob, sorry but mine has an FVP2003/02 which is flat on top and I'm pretty confident is the original (This is the unrestored car). The date on it is 5/66 which would seem to go with the build date of August 31, 1966 for the car.

It has a spring, a metal disk with center rod (which matches the guide in the center at the bottom of the PCV body) and then the rubber diaphragm. Given the design I would think you would need the metal part.

Jay and Aaron, I'm curious what the dates are on yours (And Aaron's part number)?

Bob, can you post a picture of your dome top one? I don't think that I've ever seen one like that. My wife's 1968 Spitfire had a flat top one as well so that's all I've seen since my first TR4A had already had its PCV valve removed.

Scott

 

[3798j]

The date on mine is 11/66. My 1968 GT6 Mk1 also has a flat top.

 

[HerronScott]

Bob,

I just checked my workshop manual and if their drawing is accurate, I see what you mean about a dome top and it is interesting that their drawing does not show the metal disk/pintel/poppet either. Also (again if it's accurate) it also looks like the bottom of the PCV body does not have the "guide" for the center rod on the disk to position it.

Given the drawings in the workshop manual and your earlier part number (2001 versus 2003), it would appear the earlier TR4A's had the dome top. What's your commission number and do you know when your car was built? Does it have Strombergs or SU's (both of mine have SU's and were built in May and August respectively)?

Scott

 

[RJS]

Hmmm, the mystery continues. My car is a 1966 CTC/62210-LO with a build date of November 4, 1965. It has SU's. The stampings on the lid of the valve are quite faint, all I can make out is "Patent Pending, FVP 2001/02, Smith & Sons (England) Ltd.". There is no date on the body (at least that I can discern). The other interesting point about the workshop manual is not only the picture, but the instructions to clean the valve say only to "remove the diaphragm and spring..." with no reference to a metal poppet in any way.

The bottom of the PCV body does not have the "guide" for the center rod on the disk to position it, as you correctly noted. I had noticed this before too since this would allow the metal poppet to float around in the body unless it was somehow attached or fixed to the diaphragm.

This afternoon I plan to re-attach the PCV without the metal poppet inside and take a test run.

Bob
PS: I'm not so good with the photos but, I'll try later.

 

[HerronScott]

The date is stamped on the cover on mine right above the part number (not on the body). Maybe they only did that on later flat lid ones.

It would appear that they "improved" the design between the 2001 and 2003 series. I can see where the spring would concentrate wear on the diaphragm while the plate would distribute that over the face of the diaphragm. Also, it would seem the plate and rod with that center guide area might limit travel of the diaphragm although I did not have time last night to verify that. Is there anything that would limit travel on your diaphragm besides the spring?

I would agree that the metal part probably does not belong on yours. Jeremy's part that he got from TSI would seem to confirm that. Jeremy is yours a domed top one and what's the part number on it?

Scott

 

[TR3driver]

FWIW, my TR4A SPC shows P/N 143407, which TRF has cross-referenced to 13H5191.
https://www.sportscarsupplies.com/product/BREATHER|EMISSION_VALVE_13H5191_TRIUMPH_MG_BL_260508801583

Curiously enough, my factory cross-reference has it crossed to a different number, 151658 (which TRF also has listed).

Some poking about on the web shows that there were quite a few different styles used over a fairly short period of time :
(from a Mini forum at https://forum.minicooper.org/archive/index.php/t-10418.html )

 

[RJS]

Re: Calling All TR4A's - Victory Over Oil Leaks!!

Hi All,

The (very) short story is, after a several years struggle, I have solved my crankcase pressurization and oil leak problem. And it cost me nothing. This is a great day!

Now the long story...My '66 TR4A runs the Smiths FVP 2001/02 PCV valve. Several years ago my (now former) mechanic incorrectly retrofitted a poppet valve inside the PVC (I guess he felt he was doing me a favor). Several later models of the Smiths PCV valves require this poppet but, apparently the FVP 2001/02 does not. The FVP 2001/02 only has a spring and rubber diaphragm inside.

With the "serviced" PCV connected I was getting oil gushing everywhere...timing chain cover, fuel pump, oil filler cap, dip stick and rear main seal (3"-6" puddle after a 45 minute drive)! Clearly, the crankcase was being pressurized. I inspected, cleaned and tested the PCV - never suspecting the poppet did not belong inside.

I was paranoid my engine was suffering a major malady. I tested everything: compression, leak down, intake vacuum...all with perfect results. I also suspected bore wash, carbon build-up, stuck rings (I tried SeaFoam and Marvel Mystery), shot rings, removal of beneficial carbon(who knows, I was considering anything), excessive compression... The odd thing was the engine started, idled and ran perfectly with excellent throttle response. Needless to say, I was confounded.

Fortunately, I simply ran a 1/2" hose off the valve cover to vent the CC and capped the orifice on the intake manifold. This worked well but, I was still obsessed with finding the cause.

It wasn't until this past week I was flipping through my Bentley Shop Manual when I noticed the drawing of the PCV valve did NOT show the poppet. Low and behold, after checking with you guys, I ran the car tonight with the PCV in place, poppet removed and it was perfect!. I ran a 30 minute drive (on a beautiful June evening I might add) with nary a spot of oil anywhere. 20 minutes after pulling into the garage, not a single drop of oil on the newspaper on the floor. One hour later, I saw one drop. That sure beats the stream of oil from the oil filler cap and puddle on the floor I used to get.

Anyway, sorry for the long post. I am beyond happy and can only hope this info benefits some other Triumph owners.

Bob