Do a google search on lifter preload.

 

Problem is you've pretty much got a flat top piston motor with a flat top head. Unfortunately (maybe for you), 95% of 5k's in ozland are dished piston motors, which have a lower head as half the combustion chamber is usually in the pistons.

 

A reground cam with it's smaller basecircle makes things even more difficult.

 

Until you pump some oil pressure into that motor and turn it over a bit to prime the lifters, you are not really going to be able to measure the preload. Guess you could make up something to spin the oilpump over with a drill, and turn it over ith a srarter motor and the plugs out???

 

Crosses fingers for you.

Hm I think I might just put it all together, would excessive valvetrain noise happen if the preload isnt enough?

 

heres a pic, you can see that the first few rocker arms arent touching by a couple mm when i push them onto the pushrods,

 

 

it seems too much, the oil lifters can't prime that much can they?

Edited November 4, 200916 yr by anastasios

it seems too much, the oil lifters can't prime that much can they?

 

Doesn't look good at all.

 

Think it is time for a full rethink of your valvetrain/lifter setup.

:) Got your PM. That does look like quite a substantial gap doesn't it!

 

Really is a bit of a tricky one. Look like you would have to machine the rocker posts, but you really don't know how much you should take off them until you've had some oil pressure in the lifters.

 

Can't say I've ever really seen anybody build a similar combo, so you just need to be a bit of a 'pioneer' really. Atleast when you do get it sorted 100% we will all know, and then this info can be added to the FAQ for anybody who might want to go down the same track.

Lifter preload will not see a gap on your rockers at all. I can't remember but I think I went for about 40-60thou or 1-1.5mm preload. DON'T QUOTE ME

 

Anyway, you can measure lifter preload but it is a fairly painstaking process, I think I did it about 4 times before I was comfortable.

 

Basically, you start to bolt the rocker arm down so that the rocker just makes contact with both the valve as well as the top of the pushrod. For the lifter you're measuring you want to be on the back of the cam lobe. once you have just made contact, you mark the pushrod, I used a straitedge across the top of the block and made a little score on the pushrod by rotating it against the straightedge (hard steel rule) Then finish bolting the rocker arm down into place, making sure you don't rotate the cam at all, and make another mark. Measure the distance between the marks, that's basically your lifter preload.

 

It is quite fiddly, you need to be very careful about the order you do it, how you bolt it down etc. I did it for all four cylinders, checked, checked again and basically took an average of the 8 different measurements.

 

Also, I'm certain my lifters were spring loaded, so you don't need to worry about getting up oil pressure to do this.

Also, I'm certain my lifters were spring loaded, so you don't need to worry about getting up oil pressure to do this.

 

You are right Philbey, they are spring loaded to take up the slack before the lifters see oil pressure.

 

If I remember correctly I think I've seen 2 different lengths of 5k hydro pushrods mentioned on here somewhere. Must be some 5k's floating around with flat tops and hydros from the factory.

yea seems like i need longer hydro pushrods, toyota are such a pain though, no help at all, i think i might head over there and see whats in those manuals, would anyone have any ideas of what car models to tell them as they are no help otherwise

 

 

ok so i went to toyota, on their databases all their 5ks seem to have solid lifters except for the new spacia, which seems to have hydraulic rocker gear, i have the part number but the thing is that it only had one part number, and it was the only hydro 5k we could find.

 

would the dished piston 5k hydraulic pushrod be the one i need, as they have a taller head?

Edited November 5, 200916 yr by anastasios

KM36 liteace :)

would the dished piston 5k hydraulic pushrod be the one i need, as they have a taller head?

 

No, the dished piston motors have a shorter head. Half the combustion chamber is in the piston crown, so the head has a much smaller combustion chamber in it... the rocker gear sits lower/closer to the block deck compared to a flattop head.

Found it.

 

13781-13100 might work.

 

Have a look on this thread.

Edited November 5, 200916 yr by Felix

ohh yes i have read that before! totally didnt take notice, your a legend, yea it seems like they are the ones i need,

 

 

so i ring up toyota and are like yep! we will have them in on monday, grr they might as well hire monkeys

Just out of interest what are they charging you for the pushies?

 

I don't need any as I have some Tomei Chrome Moly pushrods to go in when I finally get around to rebuilding my other 5k. :y:

13 bucks each, wow where did you get those from? do they supply them off the shelf?

They're still A12 pushies, not toyota ones. :y:

Datsun freaks! :y:

ok so when installing my dizzy, am i allowed to stick a screwdriver down the hole in the block to turn the slot that the dizzy fits into, so that the dizzy can fit?

 

also what would be stopping the engine from rotating? e.g i attach a socket to the front pulley bolt and try turn it and it doesnt move? shouldnt it spin freely?

 

i have installed the longer pushrods and it all seems sweet, nice and tight.