valve clearances?
- Thread starter bombz4
- Start date
Good to have someone capable to help as well..
fumbling with crank rotations + feelerguages + large flat-blade screwdriver + haynes manual + a spanner all at the same time for 8 valves... all while the engine stays nice and hot can be a challenge.
The first time I tried it the engine was freezing after I had set 6 valves!!!
Second time around my mate was on crank-rotations and feelerguage-sliding-fit-judjing duties ...and I was on adjuster-screw and locknut duties.
Its well worth doing though a couple of my exhaust gaps were way too big before I mage the adjustments...saved fuel and increased power afterwards!
fumbling with crank rotations + feelerguages + large flat-blade screwdriver + haynes manual + a spanner all at the same time for 8 valves... all while the engine stays nice and hot can be a challenge.
The first time I tried it the engine was freezing after I had set 6 valves!!!
Second time around my mate was on crank-rotations and feelerguage-sliding-fit-judjing duties ...and I was on adjuster-screw and locknut duties.
Its well worth doing though a couple of my exhaust gaps were way too big before I mage the adjustments...saved fuel and increased power afterwards!
S
Slim
Guest
you only need to rotate it twice. set no.1 cylinder to TDC, then set no.1 inlet, no.1 exhaust, no.2 inlet and no.3 exhaust then rotate it around until no.4 is at TCD then set no.2 exhaust, no.3 inlet, no.4 inlet and no.4 exhaust
i think.........
i think.........
S
Slim
Guest
i beg to differ there bob. If you know what your doing, they'll be fine using book figures. If you set them too tight, which 15 though probably will be, you risk burning the valves out.
inmyoppinion
If you set the clearances on 100 cars (from the same production line) when cold...then ran them all up to hot...and re-measured all of the cars' clearances simultaneously then you would get statistical deviation of the clearances for HOT across all of the cars tested
This would mean a comparable deviation would result in the performance & efficiency of these 100 cars when HOT.
Since the car is used when its hot, the clearances are best set when its hot. This way the car is 'set-up' right when the engine has warmed.
If the same 100 cars were setup hot, and allowed to cool and the clearances simultaneously measured when cold then the all of the cold clearances would show a similar statistical deviation...but who cares, because the engines aren’t even running. If all of the cars were ran up to hot again and all clearances measured again (simultaneously) then all of the hot clearances would become equal again (100 cars tuned up nice)
Hell that was a confusing epic...sorry
If you set the clearances on 100 cars (from the same production line) when cold...then ran them all up to hot...and re-measured all of the cars' clearances simultaneously then you would get statistical deviation of the clearances for HOT across all of the cars tested
This would mean a comparable deviation would result in the performance & efficiency of these 100 cars when HOT.
Since the car is used when its hot, the clearances are best set when its hot. This way the car is 'set-up' right when the engine has warmed.
If the same 100 cars were setup hot, and allowed to cool and the clearances simultaneously measured when cold then the all of the cold clearances would show a similar statistical deviation...but who cares, because the engines aren’t even running. If all of the cars were ran up to hot again and all clearances measured again (simultaneously) then all of the hot clearances would become equal again (100 cars tuned up nice)
Hell that was a confusing epic...sorry
OP
OP
bombz4
Ex. Club Member
Hi guys, almost got my car fixed yet again! got a new Nippon head gasket (think thats the company) and also cleaned up my SU carb to go on instead of the webber which i may sell (Il up date my membership i got my student loan in!). Also should be getting my st bonnet back this weekend so finnaly got it sprayed up!!
So in general happy days, but im unsure with the cam if im safe to go for bobs recommedation of 15 tho cold set. I dont want another valve going, so can someone give me thier thoughts on it? will put pics up when its back on the road!
So in general happy days, but im unsure with the cam if im safe to go for bobs recommedation of 15 tho cold set. I dont want another valve going, so can someone give me thier thoughts on it? will put pics up when its back on the road!
OP
OP
bombz4
Ex. Club Member
cheers frank will go with 15tho cold or atleast give it a try.
jstone pesonally ive never correctly torqued the rocker cover, but if your talking about engine internals etc then ye you should try to correctly torque everything, with my nippon head gasket it had quite a complex guide for tightening the head bolts, and i followed that correctly. (thought it was slightly odd to correctly finish torquing the head bolts then slacken 90deg and re torque).
jstone pesonally ive never correctly torqued the rocker cover, but if your talking about engine internals etc then ye you should try to correctly torque everything, with my nippon head gasket it had quite a complex guide for tightening the head bolts, and i followed that correctly. (thought it was slightly odd to correctly finish torquing the head bolts then slacken 90deg and re torque).
should this be done one bolt at a time in the normal sequence
or do you mean back off each in reverse sequence ( whole head becomes off compression) then retorque all in forward sequence?
cheers chaps
frank
Club Member
sammohung
same sequence, the other bolts hold the head down (squeezing the gasket) while you,re pulling each bolt down to its final setting.
i would advise anyone to follow the manufacturers specs tho, its just that i have often reused head gaskets (depending on condition) and have,nt had a failure YET
same sequence, the other bolts hold the head down (squeezing the gasket) while you,re pulling each bolt down to its final setting.
i would advise anyone to follow the manufacturers specs tho, its just that i have often reused head gaskets (depending on condition) and have,nt had a failure YET
