Dave's Mechanical Marvels Blog Page

Rover V8 points Burning Out

Twice now when I have been working on the car the engine has suddenly died and refused to restart, on both occasions it was down to the points closing up - I finally figured out why. On cars of this age it is normal to have ignition points - basically a switch operated by a cam that switches the ignition coil when it's time to spark. The coil converts the pulsing 12 volt signal in to a 32,000 volt spark, best keep your fingers clear. Anyway the coil takes a lot of current, which is ok when it's pulsing but if the ignition is left on and the points are closed you have big current going through them and they don't like it.  The trick is that when the car is cranking and you need the strongest spark the battery voltage is at it's lowest and therefore the spark is at it's weakest. What used to be general practice was to run the coil through a resistor that got shorted out when cranking so the coil gets maximum available voltage at start up and then the voltage falls to about half when running. My coil had a resistor with it but I had bypassed it because when I originally tried setting it up I can't getting a decent spark at cranking.

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V8 Hot Rod - Tuning the carbs

The carbs I have for my car came with the engine, they were in a sorry state but as I had only paid 150 quid for the whole lot I didn't expect too much. I stripped and cleaned them over a year ago so was pretty surprised when the engine fired straight up and ran pretty well. I knew they were were not bang on but they were close enough for initial testing and I didn't have a carb balancer for finishing the job. That got rectified the other day when I purchased a new old stock Gunsons balancer - it's primitive but it does the job and it was very cheap. Turns out the carbs were way out, I thought that may have been the case as they exhaust gas stung the eyes a bit, always a sign of an incomplete burn. I had already checked the timing, it was spot on.

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45 Years of Waiting - Jaguar V12 Broadspeed

I was just 8 years old the first time my mind was blown by a car. I remember it well, my parents had a Cortina 1300 deluxe at the time and my Brother turned up with a 4.2 litre Jag XJ6 straight out of the factory. I had never seen so many switches or smelt so much leather, the power and smoothness of the straight six left a long lasting impression, so much so that 45 years on I still remember the registration number - JPL444K. I knew right there and then that I was a Jag man, I have had 7 since then.

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Itom Astor Competizione Frame Painting

With everything in bits I set to stripping the 65 year old paint off, it was very patchy and there was some minor surface rust where the frame was bare, it cleaned up nicely with a stainless wire brush in my angle grinder, the Dremel dealt with the few bits the grinder couldn't get at. I went with the bike's original colours of white and yellow, the white is U-Pol brilliant white gloss, the yellow is Rover Inca yellow. It was hard to find the exact shade of yellow as the paint on there has definitely darkened over the years. I tried polishing it a bit and it came up lighter but I went with a brighter yellow anyway as I believe from looking inside the little tool boxes that it was lighter before the sun spent the last 65 years dulling it.

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ITOM Astor Super Sport Competizione

Having hidden the bike so my Wife didn't smash my stupid little face in I thought I should have a look at the engine and see what I have got. It came with a really decent spare one, I know it's good because Steve got it off my mate Dave Street and he only sells good stuff. Steve hadn't tested it so couldn't say for sure but if Dave says it's good I thought that was good enough for me. I have taken the side panel off, checked the compression and the gearbox, I could slot it straight in but it has the wrong engine code for a Competizione so I want to rebuild the engine that's in there.

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Stickney Autojumble June 2024

With the last 2 events being washed out I was really looking forward to this one, despite having to get up way too early for my liking. We had loaded up the van the day before, it was absolutely rammed. I should state at this time that I had promised that I would only buy stuff for the hot rod project and that I absolutely would not be buying any motorcycles. It was made clear and I agreed that any further motorcycle purcases would be ridiculous and quite unneccesary. Imagine my dismay, therefore when Steve and Jack turned up with  an Itom Competizione project and then proceeded to taunt me with a come and get me price.There should be laws about this sort of thing. Obviously I declined and despite their generous offer I stood by my word and walked away without making a purchase. It is therefore a complete mystery as to how it ended up in the back of my van. I deny all knowledge and insist I know nothing about it.

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Rover v8 Hot Rod Stereo / Cooling System

Before I got started on the stereo and cooling system I needed to do a couple of repairs - firstly the left rear brake caliper had seized from being sat for nearly 2 years and secondly the alternator that I have never tested before proved to be faulty. I purchased replacements for both items on line, I couldn't find an alternator the same as the one I originally used so new brackets and a new adjuster had to be made. The caliper was much easier, fit, bleed, test, paint - the easiest job I have had to do in a long time.

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Rover V8 Hot Rod - 1 step forward, 2 steps back

I guess it had to happen, progress was steady but a couple of problems cropped up that soon put a stop to all that. The first problem showed itself when I tried to move the car forward half a foot so I could glue the magnets on to the propshaft to activate the speedo - the left rear wheel was solid. I found out the caliper had seized and no amount of brutality would shift it, definitely a bin job, a new one is on order. I found one for under 40 quid so it's not the end of the world but it has stopped me from attempting to move the car under it's own power for the first time. Never mind, that day is not far away.

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Rover V8 Hot Rod Progress

I have spent a lot of time on the hot rod recently, the engine is now running, I believe the car would drive and stop, I could actually try that if it ever stops raining for long enough. Both exhausts are made and fitted as far back as the silencers, I still have to make a couple of pipes to exit the gasses near the rear wheels. I will have to check the noise level at some point, it sounds just like I wanted it to, which has happened more by luck than judgement but it may still be a wee bit too loud for the IVA requirements. It will sound louder in the workshop than it will outside but I need to measure it to avoid a needless failure on test day  a retest is a 5 hour round trip and a 90 quid bill.

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Rover V8 Powered Ford Prefect First Start

Well it's been an incredibly busy day today, only intended to spend an hour in the workshop but that hour turned in to about 12. My intention was to do one side of the exhaust as some gasket material that I had been waiting for arrived yesterday. Instead I spent the afternoon under Paulo's van, which needed an oil change and the Delta Integrale which needed the newly arrived brake pads fitting. Sunday was dark and dismal so we didn't go out anywhere, a day in the workshop was the only option. The exhaust on the passenger side was tackled first, when done it looked splendid, it all worked out perfectly, nice and simple, one single box from a Jag XJ6, some 48mm pipe, a mandrel bent stainless downpipe, my home made flange to mate it up to the manifold and a gasket I made from the sheet material. For good measure a smear of gun gum was applied to all joints, some proper exhaust clamps hold the silencers to the pipe, some cut down and bent 10mm bolts provided the rear fixing to which a rubber mount gives some movement to the whole shabang.

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Lancia Delta Integrale Group A Brakes and other bits

It's getting close to the Baston car show at Grimsthorpe Castle and the Integrale needs some work done if it is to star in the show. The brakes were feeling very hard and not working too well, the fuel gauge wasn't working and the engine refused to start so we had to push it on the ramp.

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Ford Prefect v8 Hot Rod Progress

The dash is starting to come together, it's mostly held in loosely at the moment as I figure things out. Everything now fits, the heater bix is in place, as is the wiper mechanism. The floor won't get welded any further back until the exhaust is in place, it's much easier to do all the fitting from the top with the floor not fitted.

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