Let's solve my 20V conversion problems

[Miguel - Newera]

Here's a source of good modern info on breaking in a newly rebuilt engine. Have recently done the same with a brand new sports bike engine and the results are encouragingly good: http://www.mototuneusa.com/break_in_secrets.htm

I'd recommend a cooler TRD thermostat which is inexpensive. Your mating face for the water pump should be completely flat (check surface against a glass table). A good gasket sealant should work well and cure the problem I should think. Make sure your radiator is well flushed, or replace it - as a lot of gunk can built up inside after 20+ years of use. The rad cap won't make much difference if uprated, it only means your release pressure is higher - but in normal healthy engine operation a rad cap shouldn't release pressure at all, even a standard one.

Sounds like the oil seal may be damaged, maybe careless fitting. Would be unusual for the crank to be damaged and cause leakage. Easy enough to pull it out once you have access from the front (remove the rad) & replace with a new one, taking care to apply a little grease to the surface where the crank will run.

Hopefully that'll cure your problems. 20V conversions can be fun if done well. These respond well to unrestricted intake, uprated valve springs, high lift 304 cams (no VVTi) a good manifold, exhaust and a proper ECU & mapping.

HTH

Miguel.