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Jim
11-04-2004, 10:45 AM
Does anyone know where I can get the troq specs for the 502 Head and Intake Bolts? I also would like to get the
sequence for torquing the Head bolts, seems their is a certain procedure with even possibly backing them off and then retorque them.

All I have found so far is 89lbs on the short head bolts and 92lbs on the long, increase at 10lb increments. Start on the inside bolts and work your way out in a "X" pattern.

Thanks Jim

DON N.
11-04-2004, 11:39 AM
I Divide Final Number Into Thirds ( If It's Ninety Begin @ 30# Then 60# Then 90# ) First Clean And Lubricate Your Bolts In Oil , Began In Center Of Head Top And Bottom Going Closest From Center , Rightside To Leftside Of Center Bolts Working Your Way To Each End Of Head . Same With Intake Except Go Side To Side From Center. ( And Retorque @ Final Spec. After Engine Has Been Run At Operating Temperture.) Oh Yeah , I Use To Use A Piece Of Cardboard With X Holes Cut To Place The Bolts , So I Wouldn't Mix The Bolts Up. Good Luck .

Jim
11-04-2004, 11:43 AM
I Divide Final Number Into Thirds ( If It's Ninety Begin @ 30# Then 60# Then 90# ) First Clean And Lubricate Your Bolts In Oil , Began In Center Of Head Top And Bottom Going Closest From Center , Rightside To Leftside Of Center Bolts Working Your Way To Each End Of Head . Same With Intake Except Go Side To Side From Center. ( And Retorque @ Final Spec. After Engine Has Been Run At Operating Temperture.) Oh Yeah , I Use To Use A Piece Of Cardboard With X Holes Cut To Place The Bolts , So I Wouldn't Mix The Bolts Up. Good Luck .
Thanks Don,
I was trying to get my hands on a Mercruiser Manual but it didn't happen. I found the torque sequence on the head but can't find a list of the exact torque specs for the Head, Intake and Rockers. Maybe someone can look it up for me if they have a manual. I have a 502 with Fuel Injection yr 2000 S/n 0L370409.

Thanks Jim

DON N.
11-04-2004, 11:48 AM
Maybe Mop Has A Diagram He Can Post With Specs. Phil You Listening Or Brendan.

MOP
11-04-2004, 01:46 PM
Hi noticed this one, the heads are 90 and the intake is 35, if it is a production block I believe the head bolts go into the water jacket so use GM head bolt sealer. I am pretty sure Bow Tie blocks are blind hole then any decent lube on the threads. I do not have a flat bed scanner or I would post he pattern. I think I can explain position of bolts! The lower set are numbered from front to rear 11 5 4 10 next row up 15 8 2 7 14 next row 16 9 1 6 13 top two 12 3 that should get you through it. Before you start take a wire or something thin and check to see if the holes are blind or into the water jacket. The manual call for 1/3 2/3 final, being the old pain I am I always do 1/4 steps on short heads and 1/5 steps on long 6 cylinder heads, put a little dab of Lubriplate on the valve tips before you slap the rockers on.

Phil

Jim
11-04-2004, 01:49 PM
Hi noticed this one, the heads are 90 and the intake is 35, if it is a production block I believe the head bolts go into the water jacket so use GM head bolt sealer. I am pretty sure Bow Tie blocks are blind hole then any decent lube on the threads. I do not have a flat bed scanner or I would post he pattern. I think I can explain position of bolts! The lower set are numbered from front to rear 11 5 4 10 next row up 15 8 2 7 14 next row 16 9 1 6 13 top two 12 3 that should get you through it. Before you start take a wire or something thin and check to see if the holes are blind or into the water jacket. The manual call for 1/3 2/3 final, being the old pain I am I always do 1/4 steps on short heads and 1/5 steps on long 6 cylinder heads, put a little dab of Lubriplate on the valve tips before you slap the rockers on.

Phil
Thanks Phil,
I think I got the pattern OK on the heads. Do they give you any torque specs for the Rocker Nuts ?
Jim

Jim
11-04-2004, 01:53 PM
Thanks Phil,
I think I got the pattern OK on the heads. Do they give you any torque specs for the Rocker Nuts ?
Jim
Onemore thing, I don't believe the bolts go into any water jackets but I will check, I was going to take a bottom tap and make sure to run it down each of the holes. The new bolts have a white type of sealer already on them, should I just use something in addtion to be safe? Any other names for the sealer your were recommending just incase I can't get the GM version.

Thanks again.

Rootsy
11-04-2004, 02:04 PM
if they are blind holes... no sealer needed... but if any of em go into any water at all i lubricate em all the same.. i use Hylomar for a sealer...

As for thread lubrication.. toss the ole oil right in the garbage and get yourself some ARP Bolt lube.. lubricate threads (if they all go into blind holes) and the underside of the bolt heads and both sides of washers if used...

depending on what head gasket you use by what manufacturer is gonna determine the torque sequence..

as for rockers.. on a hydraulic cam motor without a rocker shaft (ie. individual rockers) make sure the respective cylinder is on TDC of the power stroke and tighten each nut until the pushrod develops some slight rotating resistance between your fingers... and tighten another 1/2 turn down to preload the lifter...

J

MOP
11-04-2004, 02:17 PM
Sure am glad you asked that one! That is how the valve lash is adjusted they do not get torqued! There is a sequence to set the initial -0- lash plus 3/4 to 1 turn extra. get the engine on top dead center put your finger in the No1 hole when you feel the pressure build bring the balancer to -0-, both valves on No1 will be closed run the nuts down until the push rod has a slight bind when turning it then turn the nut one more full turn without moving the engine you can do Exhaust valves 1 3 4 and 8 Intake valves 1 2 5 and 7, now rotate the engine one full turn to what shows as top dead center -0- again. This will not be real TDC but 180 degrees out now you can adjust Exhaust 2 5 6 and 7 Intake 3 4 6 and 8. If you get humped up drop me an Email with your number I can give you a call later. Not sure what all you have done to the motor, if there is new valve train it pays to readjust valves at about 25 hours.

Phil

MOP
11-04-2004, 02:21 PM
Just asked my shop guy the white sealer is what GM is putting on the bolts to keep us from screwing up they work in wet or dry holes, it is Teflon base sealer so no lubrication is needed with that type.

Phil

Jim
11-04-2004, 02:22 PM
if they are blind holes... no sealer needed... but if any of em go into any water at all i lubricate em all the same.. i use Hylomar for a sealer...

As for thread lubrication.. toss the ole oil right in the garbage and get yourself some ARP Bolt lube.. lubricate threads (if they all go into blind holes) and the underside of the bolt heads and both sides of washers if used...

depending on what head gasket you use by what manufacturer is gonna determine the torque sequence..

as for rockers.. on a hydraulic cam motor without a rocker shaft (ie. individual rockers) make sure the respective cylinder is on TDC of the power stroke and tighten each nut until the pushrod develops some slight rotating resistance between your fingers... and tighten another 1/2 turn down to preload the lifter...

J
J,
I purchased all Mercruiser Gaskets and Bolts, so I have the proper sequence now.

One quick question, when I'm at TDC of the power stroke are both the Exh. and Int. valve closed? Is the power stroke when the piston is TDC and the distributor rotor is pointing at the proper cyl wire, Correct? That was the easiest way for me to explain it.

Thanks Jim

Rootsy
11-04-2004, 02:47 PM
J,
I purchased all Mercruiser Gaskets and Bolts, so I have the proper sequence now.

One quick question, when I'm at TDC of the power stroke are both the Exh. and Int. valve closed? Is the power stroke when the piston is TDC and the distributor rotor is pointing at the proper cyl wire, Correct? That was the easiest way for me to explain it.

Thanks Jim

Yes... for the TDC question.. as long as the rotor is phased correctly with the base... and the camshaft... OR go to www.cranecams.com and they have this procedure detailed in one of their tech notes.. it is pretty comprehensive :)

here i'll make it easy for ya ;)

http://www.cranecams.com/?show=techarticle&id=2&PHPSESSID=4ce1c1a3096978699308d5a8d437e058

since i believe all of your theads go into water leave the sealer... but still use ARP lube under the bolt heads where they contact the cylinder head. trust me.. it is worth it... ARP moly lube is the best there is... i've seen the torque studies... I use it exclusively on all fasteners that require a specific torque, unless they require a sealer then it is hylomar. you'll never get as even and repeatable a torque reading with anything else...

Also... instead of running a tap down the holes, and possibly removing metal from the threads i'd take a bolt of correct thread dia and pitch and cut 4 slots as deep as the thread up the side... use this to clean out the threads... you only want to clean teh crap out not make new threads...

J

Jim
11-04-2004, 02:55 PM
Yes... for the TDC question.. as long as the rotor is phased correctly with the base... and the camshaft... OR go to www.cranecams.com and they have this procedure detailed in one of their tech notes.. it is pretty comprehensive :)

here i'll make it easy for ya ;)

http://www.cranecams.com/?show=techarticle&id=2&PHPSESSID=4ce1c1a3096978699308d5a8d437e058

since i believe all of your theads go into water leave the sealer... but still use ARP lube under the bolt heads where they contact the cylinder head. trust me.. it is worth it... ARP moly lube is the best there is... i've seen the torque studies... I use it exclusively on all fasteners that require a specific torque, unless they require a sealer then it is hylomar. you'll never get as even and repeatable a torque reading with anything else...

Also... instead of running a tap down the holes, and possibly removing metal from the threads i'd take a bolt of correct thread dia and pitch and cut 4 slots as deep as the thread up the side... use this to clean out the threads... you only want to clean teh crap out not make new threads...

J
J,
Can I get the ARP Moly Lube locally at any parts stores? I'm located in CT if that helps. The head bolts have flanges built on them so its probably a good idea to use it.

Good idea on using a bolt, I can use the shorter ones that have threads all the way up. Plus that way I don't have to worry about bottoming the tap out and possibly snapping it.

Thanks for the link, Phil explained it pretty well and I think I have a handle on it but will keep the link just in case.

Jim

Rootsy
11-04-2004, 03:00 PM
J,
Can I get the ARP Moly Lube locally at any parts stores? I'm located in CT if that helps. The head bolts have flanges built on them so its probably a good idea to use it.

Good idea on using a bolt, I can use the shorter ones that have threads all the way up. Plus that way I don't have to worry about bottoming the tap out and possibly snapping it.

Thanks for the link, Phil explained it pretty well and I think I have a handle on it but will keep the link just in case.

Jim

you might be able to pick some up at a speed shop or something but if not here is the fastest way... pick which size you want.. you'll have it in 2 days or so...

http://store.summitracing.com/default.asp?target=esearch.asp&N=110&Ntk=KeywordSearch&Ntt=arp+assembly+lubricant

RickR
11-04-2004, 04:07 PM
Jim
All 502 head bolts have blind holes. 85Lbs

Rockers nuts on Gen V and Mark VI late model 502s with stock heads are NON adjustable. Sealant,45lbs. If lifters are pumped up I would tighten rocker nuts with piston @ TDC on firing stroke.

MPI Intake bolts 25-30lbs

Jamesbon
11-04-2004, 05:35 PM
I'm with RickR!

MOP
11-04-2004, 05:47 PM
Rick when you say late what year did they go to non adjustable rockers, I am looking at a 1996 manual its probably old like me! Called Jim to check post so he can find out what is right for his, I have no clue what year engine.
MOP

RickR
11-04-2004, 07:57 PM
MOP
Jim posted he had a 2000 502 fuel injected.

The Gen V originally came out in 1991.
All stock GM Gen V and Mark VI BBC engines have a non adjustable valve train. They use a 3/8 shouldered bolt (GM # 10114123,Merc # 10-811593) instead of a 7/16 stud. This shouldered bolt was used at least through 1999 (latest microfisch I have access to)
This does NOT include Merc High Performance engines.

To make late model valve trains adjustable, aftermarket studs are available with 3/8 bolt threads to screw into late model heads and 7/16 upper shaft for standard adjusting nuts. (GM # 12495518 or ARP)

Pic is of aftermarket ARP rocker stud with 3/8 lower bolt threads.

Jim
11-05-2004, 07:37 AM
Thanks for all the help guys, I guess that makes it a little easier as far as the rockers. Rich, were you saying to still
use like a Hylomar sealer on the rocker bolts? I checked them last night and they are exactly as you described and the bolts were very clean which tells me they didn't use any type of sealer when they assembled the engine.

Thanks Jim

RickR
11-05-2004, 02:57 PM
Some rocker arm bolts (or studs) and intake bolts go into the water jacket, so use sealant on them.

On a marine engine I also use Hylomar on intake to head mating surfaces , especially around water ports.

Jim
11-16-2004, 10:39 AM
Some rocker arm bolts (or studs) and intake bolts go into the water jacket, so use sealant on them.

On a marine engine I also use Hylomar on intake to head mating surfaces , especially around water ports.

Thanks for all the help guys, its finally back together minus the exhaust manifolds. Its amazing how much information you can gather so quickly when everyone chimes in. I pretty much finished it last night and now just have to get all my tools out of the boat and get the cockpit area cleaned up.
The only real problem I had was 3 of the head bolts had to be Chissled off, it took me about 3 to 4 hours on the first one and then I went and got a Air Chissel and compressor which helped out a bunch. Number one cyl. had a stuck exh. valve so I had a complete valve Job done on both heads.

I have to share this one thing, I finished about midnight last night and its been pretty cold at night, anywhere from 19 to 30 degrees but as I'm walking back to the garage last night I look over and can't help but laugh when I see the Snowman I had made with the triplets this weekend sitting in the front yard. Nothing like living in New England.

ToonaFish
11-16-2004, 07:11 PM
I have to share this one thing, I finished about midnight last night and its been pretty cold at night, anywhere from 19 to 30 degrees but as I'm walking back to the garage last night I look over and can't help but laugh when I see the Snowman I had made with the triplets this weekend sitting in the front yard. Nothing like living in New England.

Hey, isn't it about time for a new pic of the kids? Surely Halloween was an adventure this year...

Jim
11-17-2004, 08:19 AM
Hey, isn't it about time for a new pic of the kids? Surely Halloween was an adventure this year...
The triplets and my wife were down in FL for 2 weeks so
I didn't have my little ones around for Halloween. Our 13 year old went out for Halloween and I was able to stick around and hand candy out and check out the Pats game.

Jill did dress them up since the hotel did something for them
so here is one of the pics, not sure what Jason is checking out but I think it was the Pinata they were about to crack open.

ToonaFish
11-17-2004, 07:30 PM
Too darned cute! Wonder if this is the last year they will let you get away with matching outfits? (But think of all the fun themed threesomes that they could go as... Larry, Curly, Moe?) Thanks for the pics!

Jim
11-22-2004, 09:01 AM
Too darned cute! Wonder if this is the last year they will let you get away with matching outfits? (But think of all the fun themed threesomes that they could go as... Larry, Curly, Moe?) Thanks for the pics!

Thanks for the complement ToonaFish, we had them wear the customes from last year since we weren't sure if they would even get to go out trick or treating at the Hotel. They already started with the costumes, one wanted Thomas the train, I think the other wanted either to be a power ranger or spider man and the last one didn't real care.

The boys are too funny, they kept saying for the last two months how the boat broke down and sea tow/yellow boat came and got us. Now that I said its fixed they keep saying how their going out this weekend, try explaining to three 3.5 yr olds that we have to wait 5-6 months before we can go out again.

I hope we have a early spring.