when refitting the pistons should the 'F' be facing the flywheel end or the cam belt end? I stupidly thought that it said in the Haynes manual but it only refers to a arrow on the top of the pistons (which isnt there) or a casting mark (which also isnt here) so all I have to go by is the 'F' on the rods!

Any help would be great!

 

When I stripped my CVH the other week the F was pointing to the cambelt. I presume it meant Front.

 

hmm i was hoping it meant Flywheel!

 

ooooooooooooooooo now then!!!!!!!!

front or flywheel??????

 

Well i've put it all together with the 'F' facing the flywheel, this also lines the indentations on the top of the pistons up with the inlet and exhaust valves on the head, so lets hope i'm right!!

 

i would have thought it would be flywheel as they wouldnt face the front of the car!

 

flywheel i reckon

 

lets hope so!

 

The cambelt side of an engine is often called the "front" of the engine so in my opinion the "front theory" still stands.

But TBH I don't know which way the "F" has to face......

Good luck in finding out because when you have the rods and pistons in the wrong way it won't be running very nice......

 

i havent got a clue if it helps

 

I'm gonna be dismantling a cvh bottom end tonight, so i'll have a gander at my rods

 

F means front of engine. The front of the engine is the cambelt. This means you should have built the engine with F facing towards the cambelt.

 

Daveysaff let me know mate!
Its up and running sweet as a nut so i'm interested to know now!?

 

F was facing to the timing belt end mate

But if its running sweet the it cant be too much of a problem?

 

so does that mean he's got them in the wrong way?

 

Yes it does. I am trying to think back to why they need to go back in the right way but it's been a while since I learnt all that.

IIRC it's something to do with centrally aligning the rod on the gudeon pin. which if fitted the otherway, might wear the bearings out unevenly and very quickly as it puts pressure on one side of the bearing as it isn't in line. It also puts pressure on the small ends which then also transfers onto the bore wall.

It's probably not a problem Ford engines suffer with as much as others but you never know. I always seem to remember them being pretty universal in the way that they go together but then I've always built them knowing which way to refit everything.

 

I am pretty sure the engine I have just stripped has never been apart before hence me saying the F is deffo to the front/cambelt side of the engine.

Keep us posted tho.

 

Shit!
What a pain in the arse!!!
I cant leave it the way it is becase i know it's not right......... oh well!

 

OK...... before i strip it down to rotate them round the right way...... Daveysaff on the top of the pistons there are 2 angled declines oposite each other that are offset, did these line up with the valves? ie one under the inlet and the other under the exhaust, or where they offset the other way? (sorry if its a bit confusing, hard to say what i mean).

Thanks!

 

IIRC, getting them the wrong way will give you the worst case of piston slap ever

 

i fitted some pistons the wrong way when rebuilding (not that i knew it at the time) and had major piston slap! Sounded horrible, was like driving with totally dry lifters constantly

 

Why would you have piston slap? If the bores are fresh and the rings new shouldnt be any play no matter what way round they are surely?

But if you've both had it then maybe mine are the right way round cos the engine sounds sweet no knocks,taps or slaps

Now i'm just confused.... do i turn them round or not??!!!

 

conrods are normally handed due to piston oil spray jets built into the rods as this MUST spray the oil onto the correct side of the bore.

 

Stu, i was thinking along those lines but what side should it be spraying on inlet side or exhaust side of the engine?

 

The thrust face of the bore which will be the inlet side of the engine on a CVH.

 

if thats the case then the 'F' should be facing the flywheel!

 

Just scanned this for you from a haynes manual, the F is deffo on the same side of the rod as the arrow on the piston, which does face the timing belt end of the engine.

 

Oh! When i looked in my haynes manual i couldnt find any reference to the 'F'?!

Well now i know what i'm doing tomorrow!

Thanks everyone!

 

Hope you get it sorted mate!! What an arse!

 

two meanings >>>>>>>>

1--FOR-f**k sake!!!!!!!!!
2-FRONT OF ENGINE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!--- FLYWHEEL!!--HA-HA ---DONT GET ROCKER COVER CONFUSED WITH SUMP!!!!!------

 

F should always face the front of the engine...Always.

I'm now not sure why the hole would be facing the exhaust face of the bore.

 

DazC yeah i dont know mate?!

But i'm about to go outside and drop the sump, see if i can spin the pistons round from underneath, save me taking the head off!

 

Having the conrods the wrong way aroun dis not totally the end of the world, but if you have the pistons too, then you would have the larger valve cutout for the exhaust valve, and the larger inlet valve would hit the too small exhaust valve cutout. I don't think the gudgeon pin is offset in a CVH? However, Zetec has it offset like 4x4cossie and of course all modern engine.

 

JesseT, the pistons are the wrong way as well, and i cant do it from the bottom so...... off with it's head!

 

nightmare mate!

hope it all goes well

 

Wouldn't have been worth the risk just twisting the rods as the rings probably would have gone out of the proper gapping and could have ended up causing compression problems

 

haz87, yeah there was that risk but the chances of the gaps ending one above another is really low!! I would have risked it then done a comp test just to see.
But there isnt enough space to rotate them above the crank anyway so i'll have the head off....... again.... probably the 6th time in the last 2 years

Cheers jonnyrsturbo i hope so too mate!

 

All back together, pistons round the right way! Running sweet!