paul connor Posted March 15, 2009 Posted March 15, 2009 Ok.. any ideas? Today I noticed a slight misfire/rough run near the top of the rev range under load in 1+2 gears. I removed and cleaned the dizzy. rotor and points. cap etc when I removed the plugs they were fouled up with deposits. a white burnt colour and black.. very much caked on! So I cleaned and replaced. It ran much better, but then (this was at a friends house) it ran rough! very rough.. on the way home (25miles) it was clearing itself then again becoming so under powered and struggling under load and misfiring. Its very intermittent. but not going away! also the Alterntor light came on just the once and went out.. ? maybe not connected.. I think My points are gone? or maybe the light on the charge is right? and my front batteries are becoming low in charge and causing to misfire? Without light outside I cannot look and test. but i find a problem shared is indeed half way to a problem solved! So any thoughts? oh! 109 FFR 24V 4cyl petrol! Quote
fv1609 Posted March 15, 2009 Posted March 15, 2009 Come here & I'll test your condenser & rotor arm then sand blast your plugs. Fuel is it fresh in both tanks? Have you checked your timing & points gap? I had two difficult problems on the Shorland recently. Plenty of fuel with new fuel pump, rebuilt carb & plenty of HT. The bullet connector from the CB lead to the coil was only working intermittently & a fault on the fuel pump. The new fuel pump had been assembled incorrectly the spindle supporting the the diaphragm had not been turned sufficiently to engage it fully, so sometimes it managed to pump sometimes it didn't. Not the sort of thing you expect from a sealed box! Quote
Guest catweazle (Banned Member) Posted March 15, 2009 Posted March 15, 2009 Go 12 volt it will drive you mad:nut::trustme: Quote
paul connor Posted March 15, 2009 Author Posted March 15, 2009 Fuel is new in today.. was the same with old tank fuel so thats not the issue. Timing, not yet, Points seemed fine on a visual. but will check in daylight Condenser seems a poss! I shall get a new 12v one from Landrover tomorrow as that will work in the 24v system so im told. its more of a fitment issue. Rotor arm looked a little burnt.. I have 4 spares I shall change in the monring same as plugs I have 3 sets.. Im more confused with the build up ion the plugs? would a misfire cause this?? Quote
Guest catweazle (Banned Member) Posted March 15, 2009 Posted March 15, 2009 Paul when these 24 volt systems start playing up you have to be very diligent about setting everything up,otherwise you will lurch from one drama to another.you need to start at the beginning and make sure every thing you do and check is correct,if your not sure you need someone with experience to check what you have done.You have had charging problems.you must be 100% sure this is now correct.thats the first thing.The timing needs setting and no guesses,if you have a timing lamp you need to adapt a 12volt spark lead and plain spark plug and attach it to the screened inner cable so you can use the lamp.You need to be sure all your tappet gaps are correct,these sometimes vary with oval rollers whilst running.The carburretors are notorious for air leaks which destroys the action of the econmy devise and makes it run rich.You need to check for excessive backlash in the distributor drive and check for bobweight advance operation.The inner part of the rotor arm becomes loose and changes the timing.The classic problem is the inner spark cables going to earth through the outer due to brake down of the insulation.I have had this on NOS units never fitted.Replace the inners preferably with copper core.Condensor of course but i have found its first to get the blame but not allways the culprit.you need it checked as clive sez on the mega,this doesnt allways find the problem as i have found in the past as they very often brake down when hot.A replacement is difficult as all the modern ones i have found are crap and a NOS one is just as likely to let you down due to its age.You need to check the cap for tracking and the leeds where they are fixed in the cap.i could go on and on but in general that should do you.These old systems can drive you up the wall especially when you introduce more problems with cheap replacements or NOS.Check the simple things first and if your not sure get some help.:-D Quote
paul connor Posted March 16, 2009 Author Posted March 16, 2009 Well. Today I tackled the problem.. first I thought I would look at the Charging issues. Or the possibilty that the alternator or batteries were not charging and causing a misfire. After checking the voltmeter and realising I had left it on an drained the battery, I replaced and got to work. first check the battery voltage at rest. 17.8v? what the hell? each battery was near 18v! my first idea was to jump clear of the vehicle before they blew up! then I realised the voltmeter seemed to need a few readings witha new battery before it gave true! All seemed normal,checked the ammeter fuses and all was fine.. next step was ignition. Plugs that had been fouled and cleaned seemed ok.. so I thought lets not mess about and replaced with new plugs. on the roadtest this made little difference. POints.. I adjusted and cleaned..started the vehicle and it was 100 times worse! So I replaced the points with new ones and set up and it ran fine on road test. So it seems the points were the main culprit! I shall tomorrow pick up 2 brand new 12v landrover series condensers, as I know they fit and will do the job.. so as im passing a main dealer i shall get some for peace of mind Checked the dizzy and cap, all seems fine,so does HT leads. Gave the carb a tweek and checked all the levels and the axles/trans box. So Ol' Larry the land Rover is back on the road again. Many thanks as usual, I know there are many of these posts of mine. But I find to share and talk about a problem helps the Diagnosis to be much more accurate. Thanks:) Quote
fv1609 Posted March 16, 2009 Posted March 16, 2009 Paul, I think you need to buy yourself a decent meter otherwise you'll never know where you are if test equipment can't be relied upon. Yes replace the condenser. Failure in the effectiveness of the condenser not only impedes engine performance but leads to premature failure of the points from the effects of arcing. Anyway you must feel very satisfied, so now you won't be visiting then? Quote
paul connor Posted March 16, 2009 Author Posted March 16, 2009 (edited) The meter is fine, as long as you remember to turn it off!! it just seems to take a while to settle when a new battery is installed.. I shall be visiting in april Uncle Cliv, as I have 2 weeks off Rambo! maybe your right! I never thought of that! I'll check the water pump fuses and Bullet connectors with my meter in the morning! might be clogging up and causing a misfire?! Some times the connectors get corroded and the relay cant pull enough volts to turn the valve to let the water flow! Edited March 16, 2009 by paul connor Quote
Stormin Posted March 16, 2009 Posted March 16, 2009 Maybe its the water pump........... Not as daft as it sounds. I instantly thought overheating when you said white deposits on the plugs. Would also explain the charge light. Check the belt isn't worn and slipping. Quote
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