Piston Rods

Post by **Drax** » Tue May 20, 2014 9:02 am

are they bidirectional? so if you fit a piston on the opposite way around to another one, as long as you fit the pistons back into the block the correct way round, does it matter which way round the rods are fitted? hope this makes sense. if it doesn't, tell me

the only difference i can see is one side has an connecting rod oil hole, but that's it.

Cutz · Post by **Cutz** » Tue May 20, 2014 9:25 am

Check with the service manual buddy, that should clear it up for you

Post by **Drax** » Tue May 20, 2014 9:56 am

Cutz wrote:Check with the service manual buddy, that should clear it up for you

tried that, doesn't really mention which way round it should be apart from the pictures. only specifies which way round the pistons need to go (arrow towards timing belt) when placed back into the block.

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Tue May 20, 2014 10:10 am

Does the con rod oil hole pick up oil by washing in the sump, or from an oil spray bar? If the latter, then yes it would definitely matter which way round, if former, possibly not...

If the manual isn't specific, then it probably doesn't matter too much?

Post by **Drax** » Wed May 21, 2014 12:25 am

wurlycorner wrote:Does the con rod oil hole pick up oil by washing in the sump, or from an oil spray bar? If the latter, then yes it would definitely matter which way round, if former, possibly not...

If the manual isn't specific, then it probably doesn't matter too much?

manual doesn't seem to specify bud, and after looking i can't see any oil spray bar - plus the rods seem to go pretty low towards the sump so id guess it gets it from that

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Wed May 21, 2014 12:37 pm

If that's the case, then common sense would seem to suggest fitting them so the oil hole is at the back of the engine, going on direction of rotation???
i.e. as the ends wash through the sump, the oil holes are 'scooping' oil into themselves, rather than having it 'sucked' out?

I've forgotten direction of rotation of the engine atm but as in, if you're stood at the front of the car looking down at the engine and it rotates towards you, install them with the oil holes facing towards the back of the car rather than the front.

That's just going entirely off the cuff though - worth checking to make sure if anyone does actually know the answer!!!

(or maybe @4thgenPhil could go and have a look at the various dead H22's he has in his garage and let you know which way round they're installed???)

Post by **Drax** » Wed May 21, 2014 1:20 pm

wurlycorner wrote:If that's the case, then common sense would seem to suggest fitting them so the oil hole is at the back of the engine, going on direction of rotation???
i.e. as the ends wash through the sump, the oil holes are 'scooping' oil into themselves, rather than having it 'sucked' out?

I've forgotten direction of rotation of the engine atm but as in, if you're stood at the front of the car looking down at the engine and it rotates towards you, install them with the oil holes facing towards the back of the car rather than the front.

That's just going entirely off the cuff though - worth checking to make sure if anyone does actually know the answer!!!

(or maybe @4thgenphil could go and have a look at the various dead H22's he has in his garage and let you know which way round they're installed???)

oh I know which way round they are installed, but im just questioning whether it is important to have them the "usual" way round, or does it make no difference

tbh I will prob get the rod swapped anyway just in case - IF it turns out to be a problem, its a hell of a problem to have once all built lol!!

Post by **Merlin** » Wed May 21, 2014 1:30 pm

You could either ask on the FB Honda Prelude page or send Rich at PAW a wee message. He has just broken his arm/hand so might not be in the shop.

Post by **Drax** » Wed May 21, 2014 3:57 pm

after more research it seems that it allows oil in then throws it out of the top of the rod so it hits the bottom of the piston
for cooling, so for that plus consistency I shall get it reverse back around. cheers guys. merl, ive emailed Rich at PA about something else and had no response yet so I wont bug him with anything more at the moment until he has a little free time

... which is probably never lol!!

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Wed May 21, 2014 4:07 pm

Drax wrote:after more research it seems that it allows oil in then throws it out of the top of the rod so it hits the bottom of the piston for cooling

yes - that rings a bell now (not H22 specific where my 'internals' knowledge is limited, but from another engine I've looked at before!)