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baffled sump and flooding carbs


jaybee

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Hi Guys

Anyone have any info on baffling a spit 1500 sump? My car suffers from severe oil starvation/total lack of oil pressure on uphill left-handers during 'spirited' driving. I have searched the internet for solutiions, but I can't find any specifics on how to baffle the sump. I'm aware that there are 2 types of oil pump, but I don't know which is the better, or if either will cure the problem.

I have also noticed a srong smell of petrol on left-handers when the car is under high cornering forces. I can only assume that the carbs are flooding, possibly due to the float(s) jamming.This concerns me because the exhaust is on the same side as the carbs, and there's an obvious risk of fire. And no, I don't want to slow down, because I enjoy driving my car too much!

If anyone has any possible solutions, I would be most grateful if you would reply to this post.  Many thanks.

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Our friends over the pond do exactly that for various types of racing (e.g.nascar). Sounds a bit complicated for me. I'd be happy just cutting some sheet metal baffles and tacking them into the sump, so long as I knew how big to make them and where to put them!

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The GT6 Triumph Competition Manual produced by Triumph for US SCCA racers & enthusiasts has a section on fabricating a baffle for the sump of the GT6, & also a section on modify the oil pump pickup.  I'd think if you could get a copy of the manual for the Spitfire 1500 from US ebay or get hold of someone who has one already there is a good chance it also has a section on baffling the sump.

If you want to smite it with all the power of science, you could get a sump baffle & crank scraper from Ishihara-Johnson, who are the real deal:
http://www.crank-scrapers.com/Triumph_spitfire.html

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Hello Bainzy,

it's very easy to do with a welder and so much more difficult without so I suggest finding a spare sump and getting a local fabrication workshop to do the job for you. Basically you want a series of walls with cutouts and then a covering flat sheet, a ceiling if you like, low enough for the crank not to foul it. The oil pump will determine where the holes need to be.
It is possible, if your fabrication skills are good enough, to do it without a welder.

One old fashioned cure for oil surge was simply to overfill the sump, but you need to be sure that it's not too full so the crank is running in the oil as this can aerate the oil and lose your oil pressure.

Alec

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The surface baffle should be just at the level of the oil in the sump at rest - you can work out where that is from the dipstick.
It needs to have a space between it and the sides of the sump 1/4" wide, to allow oil to drain back into the sump, and holes fot the 'stivck and the oil pump to go through it.   The edges to those holes and the edges of the plate should be turned down for a 1/4" to deter oil flooding back up.
Then vertical baffles can be mounted on the surface baffle, in front and behind the oil pump pick up.  Again, 1/4" spaces between their edges and the sump sides and bottom.

You can weld the surface baffle to the sump, but themn how will you clean it in the future?   Better to follow the OE Triumph technique.   Later saloon sumps had a surface baffle, with a large wire gauze insert, that was clipped into a flange welded into the sump.    Weld small steel clips into the sump, two each side, to rest the baffle onto and that can be folded down over the edge, so it can be levered out later to clean up.

I posted pics before, but if you wnat............

John

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Many thanks guys for the replies.

Nilfisken - your pics seem to be a fairly straightforward mod which is within the realms of DIY. JohnD - if you could post your pics (again!) please, I would really appreciate it. And Rotoflex - the link you posted was very interesting, but just a tad expensive for my taste.

Has anyone come across the second problem (carbs flooding on hard left-handers)? I have owned and run Heralds and Vitesses previously, but never had this problem before. Having said that, I didn't drive them as hard as I do the Spit. I think the problem is due to either the fuel surging to the outside of the float chambers, or the floats sticking to the side of the float bowl when subjected to hard cornering forces. A possible fix might be to turn the float bowl tops so that the float hinge is in a different place. Anyone have any comments?

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These may be the photos to which JohnD refers:
http://club.triumph.org.uk/cgi-bin/forum10/Blah.pl/Blah.pl%3Fb-autotest/m-1304350209/Blah.pl?m-1275760598/s-all/#num16

Here's one Will began & manfully abandoned before it turned into the tar baby: "Firstly, the baffled sump I nearly finished had to be abandoned because it had issues with the screen touching the crank."  Good idea to start with an extra one in case it becomes apparent that things won't work:
http://club.triumph.org.uk/cgi-bin/blogs/blogview.cgi?blog=490452#17

Here's a Google search link to mentions of sump baffles on the forum:
http://www.google.com/search?as_q=sump+baffle&as_epq=&as_oq=&as_eq=&as_nlo=&as_nhi=&lr=&cr=&as_qdr=all&as_sitesearch=club.triumph.org.uk&as_occt=any&safe=images&tbs=&as_filetype=&as_rights=

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Thanks for the comments piman. I must admit I have never checked the fuel level physically, although the float level has been set and subsequently checked, and is spot-on. The needle valves are the viton-tipped  variety - I have found that they seal better and are less prone to leaking/flooding. The engine runs extremely well, and the carbs normally behave themselves perfectly. It's just this one (extreme) situation where I have problems. I like to make use of the car's good handling, but the fuel thing does tend to limit the possibilities. I suppose I should rig up some way of checking if it's just one carb or both that floods - it might help to arrive at a fix.

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