Tappet reinstallation

[Chimjunkie]

Quick question. Upon reassembly, can hydraulic tappets be reinstalled dry? Will they eventually prime and work properly when the engine is run? or is it an absolute must that they are filled?

[Chimjunkie]

rev-erend said:

So have they still not pumped up..

How often have you run them and how long for ?

Only had the engine running for several sessions of several seconds due to lack of oil pressure on the gauge (gauge moves a tiny bit. no oil pressure warning light on). Prob need to give it a little rev, but need to play with distributor to improve timing guestimate. Obviously engine very tappety because they are dry. This noise together with my knackered manifolds and the possible oil pressure issue is making me a bit timid! Battery now fully charged again so shall have another play tomorrow.

Assume i would need to run engine a 2500rpm ish for a while to get tappets sorted..

[Chimjunkie]

falcemob said:

Assuming you didn't fit the tappets completely dry, you did smear them in oil and squirt oil in the guides didn't you, then you should have no issues giving them a few seconds to fill. I would think around 10 to 20 seconds would suffice. After that if you still don't have proper oil pressure and they haven't filled then start panicking. Fullish pressure should build up on tickover, 2500 may be a tad excessive for a 1st start if it's a new build.
Edited: I would spin the engine over with no plugs in for around 30 seconds to minute with a good battery first to see if they fill.

Edited by falcemob on Saturday 25th October 23:25

Tappets dry inside but oiled on outside. Plus also poured oil all around rocker shafts, down into tappets and over cam shaft. Engine not a complete rebuild. Only took off one cylinder head and replaced new timing chain and installed adjustable pushrods. Also, as said above, the engine has already been run for several sessions of 10-15 secs to see if oil pressure gauge moved. Mostly worried that oil pump is not priming (serpentine).

[Chimjunkie]

Yuxi said:

Why do you need adjustable pushrods if you have hydraulic tappets?

Edited by Yuxi on Sunday 26th October 05:04

The preloads still need setting. usually with shims. I always had one or two tappets which were noisy and wanted to set all preloads individually.

[Chimjunkie]

Steve_D said:

The RV8 is famous for the oil pump not priming.
There are two ways around this.

Take the pump apart and pack it with Vasaline. Then turn over with the plugs out.
or
Take out the dizzy and make yourself a drive shaft to put in an electric drill and spin up the oil pump with that until you have pressure.

Steve

This i have heard, but assumed that this only applies to the older oil pump design. The Serpentine engines have a crank driven oil pump which should self prime. It's a 6-7 hour job to remove the timing cover on a TVR Chimaera unfortunately so dont want to take apart again unless i absolutely have to. Have read that oil can be pumped manually back up through the oil pressure sender?

[Chimjunkie]

Thanks guys for the input.

How about something like this for pumping oil into and around the engine?

http://cgi.ebay.co.uk/1-2-DRILL-HOSE-PUMP-FOR-POND...