What I did and did not do today !

[Harry]

Today, I was going to give the twin SUs a good talking to, but the sulky little blighter would not start, the battery had once again gone flat, so I put it on charge and did a few jobs on her, nipples first, remove the paint from them and give them a bit of grease, then I removed the faceless, face off radio ( Possible cause of said flat battery ) then I refitted the amp meter as it kept falling out of the dashboard. I then removed the fan ( Cabin Heater ) that while providing a small amount of warmth to the occupants, would also pump all the engine fumes, including any escaping Co2 into the cabin, and Gawd knows what would have happened should there have been a petrol fire in the engine bay ?? ( Who thinks of these ideas ?? ) 7" dia hole now blocked up, this should help with the engine noise too. Then off out for lunch in my trusty Mondeo diesel, the Marlin don't like leaving the garage at the moment !

[Harry]

Today in Marlin world I mostly -

Fitted new spark plugs and new leads, the plugs were working but of unknown age, and the car was sporting odd leads, some twice the length required, I had a quick look at the SU's once again, and found one throttle screw was threaded ( Lock nut us ) so I need to find a pair of new screws ( Look like 1/8 UNF but I'll check this later, I have some BA's that may just do the job ?? I also need a new seal for the rocker box cap. Also a nice new thermostat to replace the one that was not there, fresh coolant, a new gasket and housing too as it was a tad rotten, and that's it !

[stevejgreen]

Re: Today in Marlin world I mostly -

Sounds like someone may have taken out the thermostat to help with an overheating problem. Not unusual for Roadsters.
I have compiled a document of what I think is a complete on the cures for overheating at http://www.keepandshare.com/doc/4039...34-pm-48k?da=y

[Harry]

Re: Today in Marlin world I mostly -

Hello Steve, Yes I agree, it's quite possible someone thought a trick like that would work, but as you know, given the right circumstances it would over heat, and of course the engine would be heavier on fuel as it would very often not be running at it's optimum temperature ? That said, I had the engine run for a long while to check the electric cooling fan worked, also the temperature sender unit etc, and of course checked for leaks, and all seems fine ! I will check out your site as time cranks on !

[Harry]

Today at Marlin world I mostly -

Looked at it, scratching my chin ( As one does ) because my new bit's have not arrived from ebay, so, I've come to the conclusion that the engine may be a Marina, or an MGB, or a Marina with MGB bit's on it, a sort of "wannabe" a MGB ? The distributor is not a Marina distributor, or an MGB distributor, but it is a Lucas distributor ( New one in the post ) and as for the twin SU's -- 1 3/8 orifice and a linkage that also does not match the Marina or MGB of that period - 1969 - 72 ? ( As far as I can tell at the moment) I suspect they came from an older vehicle ? And a radiator from God knows what, I thought it may be a Viva, as it's a close match, but not quite there. So much to think about ---- in the bath -- beer in hand !

[stevejgreen]

Re: Today in Marlin world I mostly -

According to MGB owners there is a risk that the water pump will cavitate, i.e. struggle to pump against low resistance. There is some suggestion that this could cause overheating around number four cylinder.

[Harry]

Today in the Marlin's den, I made a lot of noise and ---

Fitted my new " Powerspark electronic distributor ) and HT leads, after a bit of fiddling and checking of the timing I give the engine a crank over and off it went, but the timing was a little out and the SUs need a good talking to, so I switched off and had a quick play with the SUs, I replaced the threaded throttle screw / nut on the front SU and replaced the seized throttle screw / nut on the rear SU, I roughly set them up then cranked up once again, after a spot of popping, banging and adjusting the engine started to settle down. I just need to get the strobe light on it, then decide what to do with these old SUs. First impression of the powerspark distributor is that it is an upgraded version of what was on the car, and the car certainly starts with more enthusiasm, but the clamp supplied with it is not as robust as the old clamp, but it does the job.
After another check of the old distributor, it does say Lucas patent, but no number, so there we are ?

[Harry]

Today at Marlin world I mostly -

Was surprised at how well the old cloncker started from very cold now she's fitted with her new distributor, I checked the ignition spark and it's far better than I had with the old distributor, so once warmed up I got the strobe out and adjusted the timing as best I could, the strobe light was not as strong as I would have liked and I could not get it any closer to the pulley unless I removed the electric fan, once done I had another crack at the twin SUs. The engine now starts and runs better, but the real test will be on the roads in this area ( All hills and bends ) So, I now require some new filter housings as the old ones are falling to bits, but I don't know what carbs are fitted, they look like HS4 s but the orifice / bore size does not match anything I've seen, I've measured these at 1 3/8" at the front of the carb ( would this be the correct place to measure them ? ) but as far as I can find out these carb sizes are in increments of 1/4 inch ?? Are there any carburetor buff's out there ?

[stevejgreen]

Re: Today at Marlin world I mostly -

From www.sucarb.co.uk http://www.sucarb.co.uk/TechnicalDetail.aspx?id=94 clearly you are correct in 1/4" increments.

[Harry]

Re: Today at Marlin world I mostly -

Thank's for that link Steve, I can now see that the Orifice is measured from the engine side and that it is / must be tapered, seem's that I have got HS4 x 1.5 inch after all - Great !

[Harry]

Overcome with excitement

Oh yes, I was overcome with excitement ( I'm a sad git ) after a number of email's, that went something like -- where the hell are they, my 10" landrover wipers arrived from ebay, so tonight's mighty job is fitting them, should occupy 1 - 5 minutes of my time, then I'm up to my gonads in fitted kitchen for the next few weeks - - joy !!

[b_caswell]

Re: Overcome with excitement

Hi Harry,

From experience make sure they clear the hood cantrail. Too late when it starts raining.

[Harry]

Re: Overcome with excitement

Thanks for the tip, to be honest the wipers are the correct size but the fit on the arm is as poor as the worn set I removed, the arm being too narrow by about 3 mm. I suspect a bodge is on the table !