Lord Flashart Posted July 18, 2011 Report Share Posted July 18, 2011 Well took the car for it's longest drive yet today. It was all of about twenty miles! It's still running at the top of the temperature gauge and the oil pressure dropped to 20 psi at 2000 rpm and only achieved a max of about 40 psi at 4000 rpm. I've changed the pistons and liners and the cylinder pressure is still only 125psi on all four. As a result performance is ****. My TR3 would have ran rings around this car! I've fitted a new oil pump. I've crack tested the head The engine also sounds as rough as anything at high revs. The only thing I've not changed is the main bearings and the camshaft. I'm thinking that I should just pull the engine again and go through it to try and see what the issues is, changing the main bearings while I'm at it. Trouble is I've got three weeks until I get a hip replacement and then I won't be working on the car or driving it for a while. The other option is to slam the garage door on the f#%^ing thing and forget about it until the spring, which I'm very tempted to do! Sorry for the rant. But almost at the giving up point with this car! I loved my three, starting to hate this 4! Paul Quote Link to post Share on other sites
Smokey Posted July 18, 2011 Report Share Posted July 18, 2011 Hi Paul, it can be frustrating - I've been there. I had my engine rebuilt ($$$) by someone totally incompetent a year ago,lost a season of driving and then had to have it redone correctly, and now, almost six years after I bought it, my car is finally running right. I've driven it about 2500 miles since the spring. My TR4 had symptoms similar to yours after the first "rebuild" and it involved debris jamming the pressure relief valve partially open. The overheating could be due to 50 years of corrosion build-up in the block and radiator. I had my block internals cleaned properly and had the radiator recored, and now the temperature never goes above 185 even in 90 degree weather. If you do the main bearings, it would be worthwhile to very thoroughly clean the block internals. British Parts Northwest will sell you a new camshaft for $208. Good luck. And by the way, a hip replacement is not a big deal - I had mine done 11 years ago. Quote Link to post Share on other sites
graeme Posted July 18, 2011 Report Share Posted July 18, 2011 (edited) Paul, Someone may correct me, but assuming everything else is OK, some of your symptoms could be atrributable to the cam timing being off. Poor performance, overheating and poor compression can all be affected by cam timing, has this been checked? I wouldn't worry about the oil pressure at the moment, there is good reason why most cars don't have oil pressure gauges now. They are otherwise known as the 'worry' gauge!! The flow of oil is far more important than the pressure. My car has oil pressure which varies for no apparent reason, on our recent trip to California, one day it wouldn't go over 40 and dropped alarmingley to 10 psi at tickover, the next day it was normal at 40 psi tickover and 70 running at 3000RPM. Hope this helps you. Cheers Edited July 18, 2011 by graeme Quote Link to post Share on other sites
Lord Flashart Posted July 18, 2011 Author Report Share Posted July 18, 2011 Cheers Graeme, Sitting here with a Boddingtons in my hand, I was thinking about the cam timing and wondering if that was my problem! I guess I could take the timing chain off and re-set the cam timing as per the manual and see if that helps. Cheers Paul Quote Link to post Share on other sites
graeme Posted July 18, 2011 Report Share Posted July 18, 2011 Mmmmmmmmmmmm, Boddies, cream of Manchester. Enjoy, I'm on anti-biotics at the moment so no alcohol. Cheers Quote Link to post Share on other sites
Lord Flashart Posted July 18, 2011 Author Report Share Posted July 18, 2011 I'm not supposed to drink either. I'm on morphine for the bad hip! I treat myself to one pint once a week!! I'll look at the cam tomorrow and let you know how I get on. Paul Quote Link to post Share on other sites
RogerH Posted July 18, 2011 Report Share Posted July 18, 2011 Hi Paul, how long has your hip been dodgy. Mine started May 2010 and got a little worse last Christmas. I'm going in on Aug 1st for the new joint. I've been taking paracetamol for the discomfort, yours must be quite painful if your on Morphine. I've got the same pressures as yourself. I'm rebuilding a TR4 and want to get it MOT'd before the end of July as August will very none productive - I think I will miss the deadline As for your engine - I really haven't a clue, sorry. All the best with the op. Roger Quote Link to post Share on other sites
Lord Flashart Posted July 18, 2011 Author Report Share Posted July 18, 2011 Hi Roger, Mines been on it's way for about eight or nine years. I injured my leg whilst in the navy and it's be steadily getting worse. They didnt want to change it too early due to my age (37). Now it's got so bad that I can't walk at all without the morphine. It's a years waiting list here in BC but I'm finally getting done on the 8th of August. I was on the verge of coming home to get it sorted out as it's a service injury I get a queue jumper on the NHS. It would have meant staying at my Mam's house while recuperating and that would have pushed me over the edge! Good luck with yours too. Paul Quote Link to post Share on other sites
Red 6 Posted July 18, 2011 Report Share Posted July 18, 2011 So back to the problem then.......... It seems to me there are 2 symptoms the oil psi and the compression. I have just finished a 4a with a freshly rebuilt engine. The compression psi was 150-152 across all the cylinders. The head had also been rebuilt, hence the high even pressures. The oil pressure was an immense 70 psi which I thought was way too high. After running in this dropped a little but not much. It seems to me that rather than closing the door on the problem it would be better to do a few tests to isolate the cause. Re the compression psi: If the head has been de coked or even rebuilt are you sure the valves are all seating correctly? Try a wet and dry test to isolate the rings from the seats. If there is no difference then perhaps the engine you have is a low compression engine. The cure is to skim the head to get that compression back. Re the oil pressure: My experience with 4 cylinder engines is limited to a 3a and a 4a both with rebuilt engines. As far as i remember you can adjust the oil pressure by the adjuster on the oil filter head. On a 6 cylinder engine all you need do is stretch the spring or make sure the valve is seated properly by lapping it in. As far as checking the cam timing, you do not need to strip the engine down, just use a DTI to establish the relative position between the cam, crank, and timing mark. My 3a had a real problem with overheating which merited a complete stripdown and an internal attack with a pressure washer and jet lance. This yielded a large maxwell house jar overflowing with rust and debris removed from the block. I fitted new pistons and liners, stripped and cleaned the head (no valve guide wear noted) and reassembled. It went like a dream and never overheated. So I presume that when you changed the pistons and liners you did something similar. If the car is still overheating perhaps it is a water pump/thermostat/radiator issue rather than clogged waterways in the block. The 4a I have just completed has a thin belt conversion and pacet electric fan with a kenlow controller which work a treat. Good luck with the hip, friends have had it done and were back to normalish in weeks Quote Link to post Share on other sites
Lord Flashart Posted July 18, 2011 Author Report Share Posted July 18, 2011 Cheers Red. You are right, when I fitted new pistons and liners I cleaned all the **** out of the back of the engine. The head I just inspected and filled the combustion chambers with petrol and left it over night. As there was no leak down I assumed they were good. I'm kicking myself now for now stripping the valves out and at least re-seating them. However, before the strip down, wet tests showed good compression and I found all the top rings were broken so I though that was the fault. Was there even a low compression engine available in '62? It does seem odd that all cylinders are exactly 125psi. The oil pressure and overheating I'm sure are related. On start up the car shows 70 psi and only after a number of miles does the pressure start to drop, along with the temperature rising. How would I check the valve timing with a DTI? I was going to remove the front cover and set it all up as per the manual. Is there a chance that the chain has jumped a tooth? If I can't find anything today, I'm going to pull the engine and start a total strip down. I'm getting bored with 85mph being my top speed!! Cheers for the help Paul Quote Link to post Share on other sites
stuart Posted July 18, 2011 Report Share Posted July 18, 2011 (edited) Low compression engines were available virtually from the start for certain countries with poor petrol. (7:1 I believe) But I think that was normally achieved with an extra plate fitted between gaskets. Stuart. Edited July 18, 2011 by stuart Quote Link to post Share on other sites
Lord Flashart Posted July 19, 2011 Author Report Share Posted July 19, 2011 Well, reset the can timing in accordance with the Haynes manual. It definitely runs better and the comp is up to 135 per cylinder so an improvement of 10 psi. Its still running hot. The oil pressure is still frightenly low at idle. It was idling at around 600 rpm. I've moved it up to around the 1000rpm to inprove it a bit. One significant discovery though. Dry comp tests bring 135psi on all four. Wet tests now result in 150 to 170 psi. Now before I mucke with the timing wet tests made no difference. So here is where I think I am. I've somehow managed to break every top ring on installation or there is a problem with the rings supplied and the problem has been somewhat masked by the cam timing also being out. The hot running may or may not be related, but the low oil pressure is definately a function of the cooling problem. I'm going to order a new set of rings and a head gasket tonight and see how that improves things. Paul Quote Link to post Share on other sites
RogerH Posted July 19, 2011 Report Share Posted July 19, 2011 Hi Paul, regarding the compression. on spinning the engine did you - Remove all spark plugs. Spin the engine apprx 5 complete revs. Have the throttle wide open. Not doing the above will/may give you a low reading. Roger Quote Link to post Share on other sites
johnny250 Posted July 19, 2011 Report Share Posted July 19, 2011 Hi Paul, Overheating and poor performance....Could it simply be severely retarded ignition?? john Quote Link to post Share on other sites
Lord Flashart Posted July 19, 2011 Author Report Share Posted July 19, 2011 Cheers guys. I test the compression exactly as described Yesterday I reset the cam timing and reset the ignition timing. The car was performing much better and to start with was pinking when in forth going up hill. So I backed it off a few degrees at a time until it stopped pinking. As a result I dont think the ignition is retarded. Something that did occur to me last night is that I may have an air lock in the cooling system. I'm going to try and burp it today. Still doesnt account for the low compression though. Cheers Paul Quote Link to post Share on other sites
Lord Flashart Posted July 19, 2011 Author Report Share Posted July 19, 2011 Well burped the cooling system to no avail. Changes the bellows thermostat to a modern type and fitted a bypass restrictor. Ran even hotter. Removed thermostat completely and left in the restrictor. Temperature perfect on the middle of the gauge! Now I hate to run without a 'stat but anyone know why it's overheating with them in? Test both units and they both open in hot water. The sleeved version is a 68degree model and the modern an 82 so it makes sense that it ran hotter with the modern fitted. Oil pressure still seems strange. On start up it's fine. Then on driving if gets steadily lower to the point when I only have 10 psi at idle and about 35-40 at 3000rpm. Thing is this all takes quite while. It's a twenty minute drive from home into town and it's just starting to drop after the twenty minutes at 60mph. I'd have thought the oil would be hot and have a thinned out long before then. Before I tear the hole thing to bits I'm going to investigation the oil filter assembly. This trouble started when I put synthetic oil I the thing and changed the oil filter. I've ditched the synthetic oil but I'm wondering if I buggered something up in the filter when I changed that! Paul Quote Link to post Share on other sites
littlejim Posted July 20, 2011 Report Share Posted July 20, 2011 The old car my Kiwi fellow students used to loan me over Xmas, while they went back home, used to give similar (but worse) symptoms. Over the 50 mile drive to and from Sydney the oil pressure would gradually drop to almost zero after about 25 miles. After letting it cool down completely I could do the other half of the journey. We knew it was the big ends because of the noise and advice from all and sundry. Quote Link to post Share on other sites
Lord Flashart Posted July 20, 2011 Author Report Share Posted July 20, 2011 Big ends are 40 miles old so I seriously doubt that is the problem!! Unless moss screwed me with **** parts of course! Quote Link to post Share on other sites
stuart Posted July 20, 2011 Report Share Posted July 20, 2011 Have you checked the clearances on the oil pump and the connection on its drive shaft. Stuart. Quote Link to post Share on other sites
Lord Flashart Posted July 20, 2011 Author Report Share Posted July 20, 2011 I fitted a new oil pump when I changed the synthetic oil out. So hopefully the clearances are ok on the vanes. By the connection on the drive shaft, do you mean check it`s engaged properly. I think the problem is in that area as things were fine until I put the synthetic oil in. I only drove about 20 miles with it in and as the pressure was low I assumed it was the oil and got rid of it. Now I`m trying to back track and see where it went wrong and see if I buggered something up! Cheers Paul Quote Link to post Share on other sites
67_gt6 Posted July 22, 2011 Report Share Posted July 22, 2011 Paul, if I have followed this correctly the one thing you haven't done is run it with your old pump and 20w50 mineral? Andy Quote Link to post Share on other sites
johnsilver Posted August 2, 2011 Report Share Posted August 2, 2011 Hi Paul, just a thought, did you fit a new water pump when you rebuilt the engine? the reason i ask is that if there is any wear or corrosion on the impellar which affects the clearance between impellar and the body water circulation can be dramatically reduced. Circulation can be virtually zero with an old water pump fitted. Quote Link to post Share on other sites
Lord Flashart Posted August 3, 2011 Author Report Share Posted August 3, 2011 Hi John, I did fit a new pump and checked the clearance from the housing. I've found the fault and it turned out to be a slightly leaking head gasket that was bleeding into the water jacket. Only just enough to make it run hot and not actually overheat. This is why it was such a pain to find. I'm now awaiting a new head gasket and I'm sorting a few other bits since the engine is in bits. Hopefully I'll be driving it again soon. Cheers Paul Quote Link to post Share on other sites
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