4age Head With No Cam Caps?!%#!

[KonaTrueno723]

Alright, i bought a good cylinder head thats missing all the cam caps. The owner before me had lost them & I know how important that these stay together with the same head...i do have caps from another head that i could use, but is it advisable or not? Reason is i got new tomei cams to install. You get the picture...

[KonaTrueno723]

No one? Damn,,this might just be a question for only a machinist could answer then huh?

[Jeonsah]

Yeah man. Just take it to a machine shop. They will have to machine the caps as best as they can to fit the new cams and to make them work with your cylinder head.

[ga_goosh]

no i would throw the caps on the head and use it as is. you cant machine the cam caps with out making the oil clearances too big. there is no bearings on the cam caps to take up the extra gap from machining. just check your head and caps for galling. if it is smooth then use them if there is galling get a different set. use some assembly lube on assembly you will be fine

[morgan]

Torquethe caps per FSM. Have machine shop inspect the boes to be sure they're not off too much to Line Hone both sides. if good, have them Line Hone and have them de-burr/break the edges of the caps, where they met the head. Then have them inspect again. They might need to mix and match caps around but you should be fine.

[KonaTrueno723]

Thanks guys! The cam caps from my spare head are in excellent shape, with no galling, grooves or scratches on them.
I'll try those suggestions, but use stock cams. I won't install the new ones just yet. Yeah assy lube is a good call & the caps are numbered in order so I'll just install them in that way. I'll torque them down easy like in two stages while spinning the cam as I go. If I feel any binding, I'll stop...

[ga_goosh]

I'll torque them down easy like in two stages while spinning the cam as I go. If I feel any binding, I'll stop...

thats going to be tough to do since the tourqe spec is 9 ft/lb lol also make sure yoiu tourqe them in the correct patern and i think you will be fine

[KonaTrueno723]

I'll torque them down easy like in two stages while spinning the cam as I go. If I feel any binding, I'll stop...

thats going to be tough to do since the tourqe spec is 9 ft/lb lol also make sure yoiu tourqe them in the correct patern and i think you will be fine

Yeah,,i'll be careful.. 4-1/2ft lbs at first then pull them up to 9lbs sequentially. See how it goes..Thnks!

[KonaTrueno723]

I'm goin to torque in the caps without the cams first, & visually look for journal wear n protruding edges where the head mates to the cap. I'll mic it too,then proceed..

[morgan]

the biggest thing you need to be careful with is where the cap mets head. there cant be a step, as in the cam shifted to one side. there is some wiggle room, so you might have to play with it.

[KonaTrueno723]

the biggest thing you need to be careful with is where the cap mets head. there cant be a step, as in the cam shifted to one side. there is some wiggle room, so you might have to play with it.

10-4.. Maybe I'll just install the cam to center everything up then.. Just got the cam caps off my other head while taking a break from this bigger job I'm doin now...it's a 2005 gmc envoy I-6 4.2L alum block & head... @ only 67k, the exhaust valve in cylinder #4's exhaust chamber burnt up.. So im removing the head..Man what a bitch four fricken head bolts snapped & broke on me in the block (around cylinder #4) during removal..heat dispersment problems I heard..I googled it

[runkillerrabbit]

broken bolts arent that hard to retract.

[KonaTrueno723]

broken bolts arent that hard to retract.

Yeah I already extracted them out, wasn't too bad.

I removed the valves & springs from my 4age head, installed the stock cams & torqued down the caps. So far both cams spin fairly easy. I'll remove them again tomarrow & check the journals.

[KonaTrueno723]

the biggest thing you need to be careful with is where the cap mets head. there cant be a step, as in the cam shifted to one side. there is some wiggle room, so you might have to play with it.

Yeah i first dry installed the caps to check for any step at the mating points. There's very little you can play with on these. Stuck my finger in each journal, it was hard to tell. I ended up installing the cams anyway to center up the caps & torqued them. I did spin both cams about 30 revolutions each (engine rotation) then removed. No visible scratches or gouge marks that I could see.. Even the cams five bearing surfaces looked ok,,so i think i'm good!

Thanks for all the input guys!

[redroku87]

This is going to sound a bit stupid, but I am missing ONE cap.

Will a 4AC cap work on a 4AGE?
I have two 4ACs worth of parts laying around. How about 7AFE caps?

[morgan]

I have a few spares. PM me and I'll ship you one, need the bolts too?

[KonaTrueno723]

^^^ there ya go redroku87! Stick to 4age caps

[8Ton]

the biggest thing you need to be careful with is where the cap mets head. there cant be a step, as in the cam shifted to one side. there is some wiggle room, so you might have to play with it.

Yeah i first dry installed the caps to check for any step at the mating points. There's very little you can play with on these. Stuck my finger in each journal, it was hard to tell. I ended up installing the cams anyway to center up the caps & torqued them. I did spin both cams about 30 revolutions each (engine rotation) then removed. No visible scratches or gouge marks that I could see.. Even the cams five bearing surfaces looked ok,,so i think i'm good!

Thanks for all the input guys!

Did you use a machinest dye? There is a blue dye that you can paint on the journals that will rub off on any high spots. In a pinch I have used a felt tipped pen to color the area in question. 30 odd revolutions with no significant load is unlikely to show any problem spots without dye.
Worst case, you could have the journals "re sized" at a machine shop. what they do is mill the entire top of the head and then align hone the journals BUT your cam to crank distance will be reduced slightly and you will need cam gears (same as if you milled the head for more compression or used a thinner HG)

[KonaTrueno723]

Yea,didnt want to second guess anything w/o messing up my new cams.. i just went & took it to my machinist had it clearance checked to the head & the new cams with dye stuff you mentioned. Resizing wasnt needed.. These parts were from low mileage motors,which prob has somethin to do with it I guess..?

Heads up to members or for anyone buying used aluminum heads utilizing these type of cam cap configuration..My machinst stressed that these caps must remain together to the same cylinder head it originated from when possible

Thanks 8ton

[8Ton]

the real issue is differences in the original castings and production line machining. they machine them together so that they are "perfect" but you mix and match and s#it gets fubar quick! Its the same reason to keep your main and rod caps in the same position. Toyota did a much nicer job in the '80s than mopar and chevy did (or may ever do), but it can still ruin your day! Glad it worked out for you!