Badfrog Posted October 8, 2013 Report Share Posted October 8, 2013 Exactly it. My beloved TR4 has a tendency to blow and spit oil by the crankcase ventilation, although everything I can think of is OK. So I have a question: I used the mechanical fuel pump hole in the block to create a PCV in the form of a 1" tube going into a catch tank. I know the oilways contain an outlet designed to spread oil over the fuel pump lever and cam from the camshaft. Could it be that this oil supply is blown into the oil catch can tube by the lower block pressure? Should I use an other block exit away from any augmented oil supply, such as the old TR4 breather pipe hole still present but plugged in my 4A engine? Can I simply block the fuel pump hole and rely on the upper rocker cover exit? The spitting does not start before 4000 rpm, but that's where I like to play. Thanks for any help, Badfrog, spitting bottom driver (classy, really) Quote Link to post Share on other sites
Tom Fremont Posted October 8, 2013 Report Share Posted October 8, 2013 Hi JF, Have you considered the 4A PCV valve? These are still around NOS on ebay. There should be a port in the inlet manifold already. Quote Link to post Share on other sites
ianc Posted October 8, 2013 Report Share Posted October 8, 2013 Instead of sucking fumes into your inlet tract (as on TR4A), take a flexible tube (I use rubber heater hose) from the right side of the rocker cover (alloy covers have a pipe there), over the top of the rocker cover and either: (1) down the left side of the engine, past the fuel pump until it's about level with the bottom of the oil filter housing (i.e. vent to the road!), or (2) into a catch tank. The first option works for me! Ian Cornish Quote Link to post Share on other sites
Badfrog Posted October 8, 2013 Author Report Share Posted October 8, 2013 Tom, I don't want to use the 4A PCV that fouls the valves. Ian, If I get it right, the upper outlet going to a can or to the road is good enough and I can block the fuel pump aperture? Real nice. Will do. Thanks a lot. Badfrog Quote Link to post Share on other sites
Tom Fremont Posted October 8, 2013 Report Share Posted October 8, 2013 Tom, I don't want to use the 4A PCV that fouls the valves. Badfrog JF, Shouldn't foul if the rings are OK ( and if you avoid certain notorious fuel brands, but that's got nothing to do with PCV ) - mine aren't foul, thank you 70K miles and counting. Quote Link to post Share on other sites
peejay4A Posted October 8, 2013 Report Share Posted October 8, 2013 A modern PCV with an oil trap is what I'm going to experiment with sometime over the winter. Quote Link to post Share on other sites
ChrisR-4A Posted October 8, 2013 Report Share Posted October 8, 2013 I have been using a TR4 crankcase vent pipe on my 4A for 15 years together with a plain pipe from the rocker cover as Ian mentions. This worked very well with the original well worn engine and is now even better with a rebuilt motor. You can't have too much engine venting to help keep the oil in the engine instead of leaking out and helping it rev freely. Quote Link to post Share on other sites
Badfrog Posted October 9, 2013 Author Report Share Posted October 9, 2013 A modern PCV with an oil trap is what I'm going to experiment with sometime over the winter. Peejay, Can you elaborate? What is a modern PCV for you? Thanks. Badfrog Quote Link to post Share on other sites
stuartmac Posted October 9, 2013 Report Share Posted October 9, 2013 Does a vent pipe off the rocker cover vent the entire engine (ie including the crankcase) or just the or just the rocker area? Quote Link to post Share on other sites
ianc Posted October 9, 2013 Report Share Posted October 9, 2013 My engine has both the usual crankcase vent (the steel pipe, as fitted to the TR2/3/4) and the vent from the rocker cover, as I have described above. I added the rocker cover vent when I fitted an alloy rocker cover, which has a sealed filler cap. I wanted to ensure that there could not be any build-up of pressure or water vapour at the top of the engine. I'm afraid that I cannot say how the engine would perform with the original (crankcase) vent blanked off. Ian Cornish Quote Link to post Share on other sites
peejay4A Posted October 9, 2013 Report Share Posted October 9, 2013 Peejay, Can you elaborate? What is a modern PCV for you? Thanks. Badfrog Plugin pcv from a Jeep (Cherokee I think) which goes into a Transdapt replacement for the oil filler cap on my Offy valve cover. The pcv will go to an oil trap, probably an adapted compressor water trap, then to a vacuum takeoff. Quote Link to post Share on other sites
Motorsport Mickey Posted October 9, 2013 Report Share Posted October 9, 2013 Entire engine via the cam follower gallery, ...but not very much. Fit a bottom engine breather, favourites are via the fuel pump aperture (replace mechanical with electric pump) or remove the plug in the side of the engine near the fuel pump (TR 4/4a) and replace with TR2/3 downward facing vent pipe, or pipe either of these fixes into a "catch tank" fitted inside the engine compartment. Mick Richards Quote Link to post Share on other sites
Badfrog Posted October 9, 2013 Author Report Share Posted October 9, 2013 Mick, I am presently using the fuel pump aperture, but I was questioning the validity of the technique, re- oil droplets propulsion by block pressure. The problem is that the engine spits oil by this hole due to excessive blowing while the compressions are OK and the engine has only 15K miles since rebuild and really goes. The rings interruptions were correctly set 120° apart. Thus, I don't think it's blow-by, but then why is it blowing? As I've been out of the scene for 18 months and never drove harshly since rebuild (on account of the Missus on board), the car has been underused. Could it be that the engine is not bedded in? Should I drive in high revs for some time? Badfrog Quote Link to post Share on other sites
Motorsport Mickey Posted October 9, 2013 Report Share Posted October 9, 2013 Hi Badfrog, At 15,000 miles I would have thought your engine is bedded in, however it's worthwhile to remember that BMEP is most prevalent at the area of max torque and if you like to play in the "higher atmosphere" of engine revs it maybe you have by passed the maximum ring expansion area. If you modify your driving for a couple of hundred miles and use the torque in top gear at it's maximum area it should help the cylinder bores bed in if they are not already, and the mem sahib will enjoy the quieter ride ! As regards the fuel pump aperture I would consider a vertical flap or trap fitted before the large bore pipe at the fixing plate end on the block capable of stopping any "splash" entering the pipe and being forced out by engine pressure? Mick Richards Quote Link to post Share on other sites
Badfrog Posted October 10, 2013 Author Report Share Posted October 10, 2013 Thanks Mick, I believe you gave me the two key answers. I just have to find the max torque of this Kastner D cam and ... now for some serious speeding ... Cheers, Badfrog Quote Link to post Share on other sites
Guest ntc Posted October 10, 2013 Report Share Posted October 10, 2013 It's running to rich JF smelt it as you drove off at the IWE Quote Link to post Share on other sites
Badfrog Posted October 10, 2013 Author Report Share Posted October 10, 2013 (edited) Neil, You're right. That may be a part of the problem thru fuel washing off oil from the cylinders walls and lowering ring tightness. I thought off that too and I am currently trying weaker needles. I already went down from TS to SM and now TW, but it is not enough. I have to go down one (two?) more step(s). For a proof, the car used 9L/100 km (31.4 mpg) in the Kent trip when I'm usually down to 8L/100 km (35 mpg). Badfrog Edited October 10, 2013 by Badfrog Quote Link to post Share on other sites
Guest ntc Posted October 10, 2013 Report Share Posted October 10, 2013 JF The smell and viscosity of the oil on the dipstick will tell you Quote Link to post Share on other sites
Badfrog Posted October 10, 2013 Author Report Share Posted October 10, 2013 (edited) JF The smell and viscosity of the oil on the dipstick will tell you Nifty. Thanks Neil. You live and learn. Shoot, I have all the solutions and parts and I'm stuck home with a bronchitis. I could be working on MdW Badfrog Edited October 11, 2013 by Badfrog Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.