daimler 250 v8/ Jaguar MK II
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Discussion

allan woolley

Original Poster:

1 posts

98 months

Friday 2nd November 2018
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need help, own a 1967 daimler 250 v8, have two problems. over heating, have replaced raditor, with bigger one water pump add electic fan still over heats.
second problem carbies over hauled both eplaced all fuel lines from tank cleaned tank new fuel pump car dies when pushed hard any ideas would be of great help allan

anonymous-user

83 months

Friday 2nd November 2018
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Given what you've already done on the cooling system, and on the assumption you've discounted things like thermostat and collapsed radiator hoses etc, the most likely cause would be hard silting up of the water jackets in the block. Once this happens, pretty much anything you upgrade will not overcome that basic lack of circulation. You can check by either removing the heads and prodding a rod down the waterways or by removing core plugs and doing similar.

If your investigation proves positive then the best solution would be to acid dip the block/heads once stripped down. Proprietary "pour in the radiator scale removers" rarely have any appreciable effect once it gets to this stage.

Strugs

515 posts

258 months

Friday 2nd November 2018
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Possibly a silly question.. But.. is it definitely overheating? I.e. is water boiling over, and you're not just looking at the temperature gauge?

v8250

2,747 posts

240 months

Friday 2nd November 2018
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Allan, as per the guys notes above, first prove temp gauge is operating correctly - this is easily done by using a.n.other temp sensor/temp gauge/thermo gun [these are low cost infrared units readily available to buy and can be directed at component heat source/s].

If still reading high it's quite probable the engine/head water galleries are blocked. This is a common problem with the v8250 engines when they're not cared for [usually by previous owners]. Blockage is often exasperated by PO's who have used gasket sealants when/where they should not have done so. The sealant then blocks water flow, resulting in high engine temps.

Re' engine sluggish under load - 1. check the SU's float set up, 2. recheck air/fuel set up using a carb balancer, 3. check fuel volume + flow rate just prior to the SU fuel line 'T'.

Next, 80% of fuel problems are ignition related and the V8250 engine has lots to go wrong that will give the sluggish symptoms you're experiencing. In particular the distributor twin contactor gaps as they have a tendency to close up. Also check coil breakdown, condenser breakdown, spark plug lead breakdown under increased load + the dreaded spark plug extenders...these can often fail.

Methodically work through the above and you should find the fault.

PS temporarily change the SU fuel pump for a 12v constant velocity pump to prove operation as the SU unit's contact gap also closes up/seizes where they're rarely serviced/serviced correctly. Good luck...