Guest ade Posted June 29, 2004 Report Share Posted June 29, 2004 Hi All, MOT tomorrow and I've got I question for your collective intellect... I have a Kenlowe fan fitted, with no mechanical (crank damper instead) and the engine seems to run warmer than I'd expect. Higher than the region either side of "70" on the temp gauge. The fan cuts in but seems unable to pull the temp down to normal level - any thoughts as to why? -could there be an air lock? -The water pump is new and the rad re-cored. -Engine rebuilt and timing etc seems good It doesn't boil over but does run warmer than expected - should I woory about this? cheers Ade Quote Link to post Share on other sites
robgeev Posted June 30, 2004 Report Share Posted June 30, 2004 Ade, is the fan blowing (or sucking) the right way? Seems an obvious question, but happens all too often. Try removing your thermostat entirely-maximise coolant flow, just in case you need to cut down on restrictions, we run a 4 without one in, and it's fine, warming up plenty quickly-after all who goes out in the winter anyway? Next step can only be radiator efficiency, check how old your rad is, and how fine the fins are, and how many rows (depth) of cooling tubes there are, we had to change one to sort a very similiar problem to yours-it was hitting 100 on the motorway, now sorted, I believe Tr enterprises can supply a performance rad for you. Rob. Quote Link to post Share on other sites
JRCWeedon Posted June 30, 2004 Report Share Posted June 30, 2004 There are a number of dodgy water pumps in circulation was yours the genuine article or a cheap one? Some have too large clearances and others the wrong impeller. I bought an uprated pump with more vanes than normal from Cambridge Motorsport which works very well. Regards John Quote Link to post Share on other sites
Guest ade Posted June 30, 2004 Report Share Posted June 30, 2004 hi thanks for the replies The water pump is one from Moss, so I suppose it's a cheapie one - I'm going to put an impeller type on it as a matter of course anyway. The ard has been recored by TR-Bitz so should be the real-deal. The kenlowe (now i've re-read the instructions) seems to be ok if I set it to cut in higher it is able to pull the temp down, not to normal, but definately not boiling etc. I'm going to take it for a decent run as soon as the MOT has been passed and see how it goes. Cheers again Ade Quote Link to post Share on other sites
Guest ade Posted June 30, 2004 Report Share Posted June 30, 2004 sorry can't spell/ type "ard" should be "rad" !!!!! Quote Link to post Share on other sites
jonlar Posted June 30, 2004 Report Share Posted June 30, 2004 The kenlowe (now i've re-read the instructions) seems to be ok if I set it to cut in higher it is able to pull the temp down, not to normal, Ade Ade, Surely you mean at a lower setting? Where is the temp. sensing bulb situated, on my 6 I've re-located it to the bottom of the rad. which I find works very well. Quote Link to post Share on other sites
rayjones Posted June 30, 2004 Report Share Posted June 30, 2004 I agree with Jonlar, I was not happy with the way the fan switched when the bulb was positioned in the top hose. It only seemed to come on when the temp had risen considerably, then took ages to switch off again. Re-positioning the sensor in the bottom hose made a dramatic difference, the fan now cuts in with a slight rise in temp, stays on for 30 secs or so, cools things, and then will come on again maybe a minute later if the car is still standing in traffic! Quote Link to post Share on other sites
Dale Moore Posted June 30, 2004 Report Share Posted June 30, 2004 Check this link out before removing your stat. http://www.cruzers.com/~twakeman/TR/thermostat.htm Dale Quote Link to post Share on other sites
Guest ade Posted June 30, 2004 Report Share Posted June 30, 2004 Hi The bulb is at the top hose, as per the instructions, which seemed odd to me. The fan cuts in and stays on for ages. I'll try the lower hose and see how it is then! BTW--------IT PASSED IT'S MOT!!!!!!!!!!!!! - Reg plates by Monday. cheers Ade (a VERY happy bloke) Quote Link to post Share on other sites
robgeev Posted June 30, 2004 Report Share Posted June 30, 2004 Check this link out before removing your stat.http://www.cruzers.com/~twakeman/TR/thermostat.htm Dale This guy knows thermostats! (anorak), but he is potentially right, maybe we should fit one back in again, Carl did partially block the bypass hose (nut), but has now removed it, as cooling would seem to be good, another job for tomorrow! Rob. (not an anorak) Quote Link to post Share on other sites
marvmul Posted June 30, 2004 Report Share Posted June 30, 2004 [http://www.cruzers.com/~twakeman/TR/thermostat.htm Dale This guy knows thermostats! (anorak), but he is potentially right, maybe we should fit one back in again, Carl did partially block the bypass hose (nut), but has now removed it, as cooling would seem to be good, another job for tomorrow! Rob. (not an anorak) Should Twakeman be a guy because she knows something about cars? Twakeman is Tery Ann Wakeman. Quote Link to post Share on other sites
robgeev Posted July 1, 2004 Report Share Posted July 1, 2004 Rob.(not an anorak) Should Twakeman be a guy because she knows something about cars? Twakeman is Tery Ann Wakeman. Perhaps Twakegirl might be a better handle then? You could see how someone could be confused. Rob. Quote Link to post Share on other sites
Guest Tiggers4 Posted July 1, 2004 Report Share Posted July 1, 2004 Hi Ade, I've just had a similar set of problems regarding running hot and also a head gasket failure that I've now fixed. No.3 cylinder was compressing to 170 psi and then blowing past the gasket into the cooling system blowing coolant out the overflow pipe. I suspect my overheating problem was in part due to a head gasket leak disrupting the flow of water round the system. This is all fixed now, but mine still runs a little to the right of the 70 degrees mark. I've had the rad re-cored, new water pump (high output) from Moss, new hoses, new thermostat, and used double strength flushing agent in the block (before the gasket went). I also have a Kenlowe (what I would call first generation fan) fitted and no mechanical fan. The kenlow pushes air through the rad as it is front mounted. The only thing I don't have is the airflow ducting fitted behind the grill which I'm told does aid cooling at speed as this provides a more directed flow of air through the rad. When I've finished tidying up the wiring around the top of the grill, I'll get hold of one of these and fit it on. A couple of thoughts come to mind on this: 1) The TR4 has a large capacity cooling system. Once it gets to normal it then takes a fair amount of time to get to the mark on the right of the 70 degree mark. I've set my kenlow to trigger in once the temp needle goes past the mark. Once it comes on in traffic it reduces temperature but not to the point where it cuts out again. I don't think the lvolume of airflow being created by the fan is sufficient to bring the temperature back down to the trigger point. The other thing is that there is always a level of "tolerance" on thermostat devices which means that you might set it to trigger at 75 degrees, but it probably won't switch off until it gets back down to 70. The next time it comes on will be when it gets up to 75 again, hence youv'e got at least 5 degrees of "slack" in the system. My thoughts are that the latest generation kenlows are probably much more effecient in terms of the volume of air they shift and would probably reduce the water temp down to a point where temp sensor would cause the thermostat to cut the fan motor. 2) Modern cars have much lees coolant but more effecient radiators. There tends to be agreater surface area over which to achieve cooling and because there is less coolant in the system, the cooling processi more rapid. My feeling on this is that you could change out your kenlowe for a later type to resolve the fan being always on in traffic, but that won't resolve the temp issue at speed. If you haven't got the airflow duct fitted, you may want to try making up some temporary ducting with cardboard and see what that does. Graham Quote Link to post Share on other sites
Guest ade Posted July 1, 2004 Report Share Posted July 1, 2004 Hi Thanks Graham I hope that my head gasket isn't going (it should be brand new!) Things have improved now that I've sorted the timimg and got it to idle a bit lower. It won't idle smoothly below 100rpm yet as it's still tight. The kenlowe now cuts in at the line to the right of "70" and is able to cut out again. This was just idling in the garage on a warmish day so I think I may be near to solving it. One thing that may have helped was letting the car reach temp with the rad cap off, there may have been an airlock. Time to go for a drive I think and see what happens (if the DVLA phone back to advise me of the reg number!):rock: cheers Ade Quote Link to post Share on other sites
Tr4Tony Posted July 1, 2004 Report Share Posted July 1, 2004 Ade Might be too late but two things; 1. I run a cut out thermostat disc on BST82B - i.e. a waxstat thermo with only the disc with the 1/2 inch hole - all the rest cut off. this seems to funnel the water through the pump and the car only warms when I really give it a pasting; 2. The thermo on the kenlowe measures water at the top of the rad where its at it hottest. On my TR4a I run a kenlow but with the thermo switch actuated from the lower stel rad pipe through a tapped in sensor. MOSS sell both the pipe and sensor and they are cheap to replace (£3). No problems on this car either - if i run the bulb in the top rad hose I go up a tick on the temp gauge. This may be all that you are suffering from. Lastly even you recored rad could be poop. I has a NOS one in the car to start with an it was a nightmare - make sure its good - I suspect it is otherwise youd be boiling it up so this is the last gasp item. The 4 cyl engines will take a lot of heating up to bust them, but the main thing is to ensure that the head stays at temp as this is the weakest part - water jacket at the rear cylinder is a fav. to crack. You may also need to torque the head down as a little water leak may be enough to keep the gauge up. I had one behind the exhaust manifold which took an age to find as the water evaporated. All I could see was water loss - measure levels carefully. Regards and see you at the IW. Tony Quote Link to post Share on other sites
robgeev Posted July 1, 2004 Report Share Posted July 1, 2004 Not sure what Twakegirl is talking about with shouldered thermostats, checked ours out, wouldn't seem to be possible to fit the deep shouldered type (ie old Land Rover)? Our heads have a very shallow groove to accept disc type stat. Rob. Quote Link to post Share on other sites
Guest Tiggers4 Posted July 2, 2004 Report Share Posted July 2, 2004 Ade, Glad to hear its OK. After emailing my reply yesterday to you, I decided to order the air duct to sit behind the grille to see if this brings my temp down to 70 degrees when I'm out on the open road. My kenlowe ids pretty old by the way (probably fitted early 80''s) and I don't think its efficient enough to get the temp back down below the "trigger point". I tried to see if i could just buy a new "turbo fan" from kenlowe to fit on my motor unit, but not possible. Need to buy the whole unit as a complete assy. My 17 year old son will have another driving lesson from me this weekend (great feature of Country Mutual insurance as he is on my policy as a named driver and it only costs me £170 a year fully comp). Getting him insurerd on anything else is £1800 !! After he's had his lesson, I'll re-torque the head down, fit the air duct and hopefully thats that on the cooling side! My wife has the divorce papers ready to sign if I spend any more time messing about with it!! (only joking). Graham Quote Link to post Share on other sites
Guest ade Posted July 2, 2004 Report Share Posted July 2, 2004 hi Graham (and cheers too Tony), I took "CBU 34B" for it's maiden voyage today - and fantastic fun it was too, no rattles, handles well, engine very tight but super torquey. Anyway, the temp was above 70 all the way round, never boiled over though, Kenlowe tripping in and out. So...I called at a mechanic mate's of mine and borrowed his non-contact thermometer to check the temps around the engine, here's what I found: Thermo housing: 75 Top of rad: 68 Cylinder head: 95 (same at each) Block: 70 ish Bottom hose 40 My Mechanic mate said that if anything it was a bit cool! (temp not the car) and that the gauge is a poor design as the normal operating temp should be about 80-85 degrees. Also, the fan shouldn't cut in until 90-95 degrees to prevent boil over (remember the system is pressurised to a certiain extent and will not boil at 100, only distilled water boils at 100, so having impurities in it will raise it's boiling temp anyway) I agree that the gauge is misleading as it looks like the car runs hot when in fact it's quite normal (apparently). Another thing, the thermostat doesn't open until 80 degrees, so why have the fan cutting in below that? It's obvious when it does open as without the kenlowe on the temp still drops just after 80 degrees. I think I'm a bit paranoid about my baby! The uprated water pump's still going in though... cheers Ade (my Fiancee, Natalie, says we might not even get to the wedding stage if I don't move back into the house from the garage! - She means it too...) Quote Link to post Share on other sites
Don Elliott Posted July 2, 2004 Report Share Posted July 2, 2004 When I restored my TR3A in 1987 to 1990, I had the head skimmed and used racing nuts to secure the head to the studs in the block. These nuts are 7/8" high instead of the original nuts which measure 1/2" high. I have torqued my head a bit higher than the suggested torque specified because there are 14 full threads in these nuts instead of the normal 10. I'm sure that the racing suppliers such as Darryl Uprichard or Neil Revington could tell you all about these nuts. I have not had a head gasket problen during that 14 year period during which I have driven "TRusty" over 82,000 miles. Don Elliott, Original Owner, 1958 TR3A, Montreal, Canada http://mysite.wanadoo-members.co.uk/trebor/don3a_big.JPG Quote Link to post Share on other sites
Guest ade Posted July 4, 2004 Report Share Posted July 4, 2004 Right... after much brain-ache I've discovered why the car seems to be running hot (but isn't) Here goes then: 185F is NOT 70C, 185F is 85C. It's the Centigrade gauge that is the problem with it's "normal" region being set too low. Normal running temp is 85C (according to the manual and other texts) Ta daaa...! simple really Just need to get a farenheit gauge for a late TR4 (flat glass) and I'll be happy Cheers Ade Quote Link to post Share on other sites
Guest browserfour Posted July 5, 2004 Report Share Posted July 5, 2004 I bought a electric fan, with it I bought an inline thermostat, fits inline in the top hose, the stat is not adjustable and switches the fan on at 84 C. Check out your stat. As previously mentioned check wether your fan is a sucker or a blower. Good Luck Quote Link to post Share on other sites
Guest ade Posted July 5, 2004 Report Share Posted July 5, 2004 the fan is a blower, and rarely needs to cut in now it is set just before the lower edge of the white "100c" marker cheers 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.