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gr8fulabe
03-24-2012, 10:05 PM
Hi all,

I have a lateish '74 '40 (F155 engine), that I realized was leaking coolant into the front cylinder (number 1 I believe, but not 100% certain). I learned becuase i was trying to put in a big cover dizzy & dented side cover & pulled that plug to find TDC, and had water squirt out when I bumped it over.

so I pulled the head a little while earlier, and I can't find any specific damage to the Head Gasket, but I've bot some questions.

1. I thought they were usually a metal base, with some sort of layer over them. But when I cleaned it up, it seems to only be a metal sheet. Is that correct?
2. Is it possible to leak through the gasket without any visible signs of it being blown out?
3. There seems to be some rust or somethign inside the cylinder. I haven't tried to clean it really well yet, other than wipe it down, as it was getting dark. But how much is too much, and what is the best way to clean it, to tell if it is okay?
4. What's the very cheapest way to get this truck running again? I don't have a lot of spare cash right now if you know what I mean...

I took some pics, that I will download & post, in case they help. But I don't know if they will provide any insight.
THanks in advance!
Best,
Abe

gr8fulabe
03-24-2012, 10:21 PM
27729

27730

27731

27732

27733

60wag
03-25-2012, 07:26 AM
I'd take some Scotchbrite to the rust and polish away. If the rust comes off, great. If the rust has eaten into the wall of the cyl, you could either leave it or spend a bunch of money to get rid of it. If the the rest of the engine is original with lots of miles, just clean up the corrosion and call it good.

Inspect both the head and block for cracks or bumps that might effect the sealing of the head gasket. Inspect the head gasket with a magnifying glass to try to see the path of the coolant to the cyl. Inspect the combustion seal flange on the gasket for cracks. If you can't find any evidence of the leak or reasons for the leak, Put a new gasket on it and put it back together.

Did any of the headbolts seem to be a lot more loose when you took it apart? It may have leaked due to loose or improperly torqued bolts. Maybe it overheated? That can cause the gasket to be crushed and loose sealing stress.

The picture of the gasket looks like normal gasket construction - a perforated steel sheet with paper on both sides and a steel combustion seal. There are steel shim gaskets without paper out there but I doubt one is made for the 2F. They are usually higher cost designs for engines that are more difficult to seal.

subzali
03-25-2012, 08:20 AM
It's best to chase the head bolt holes with a tap before reassembly.

Air Randy
03-25-2012, 09:25 AM
How many miles does that engine have on it? I would seriously consider taking the head in to a machine shop and having them check it for cracks, not an uncommon problem on F/2F heads. If it has no cracks then they can check to make sure it isn't warped and they can deck it to ensure it is flat. Once you have cleaned the block surface really good, then check it with a steel straight edge too to make sure it is flat as well. If it has enough miles on it, you may want to have them do a valve job on the head to ensure the seats and guides are all good. Overall not that expensive to do. While the head is off, you should also drill out the oil galley plug, tap it then put in a threaded plug. That could save your engine later.

You can clean that cylinder up with some steel wool, then run a hone in it with the piston at BDC. It should be fine as these old tractor motors never ran very tight tolerances even when new.

Too bad you didn't run a compression check on it before you pulled the head. If a few of the cyliners were down on compression it's super easy at this point to drop the oil pan and put some new piston rings in it too.

gr8fulabe
03-25-2012, 09:49 AM
Thanks for the ideas guys!

The head gasket itself doesn't have any paper on it now. Is it possible I, "scrubbed" it off when I hit it with the pressur washer @ the coin op place?

I have no idea how many miles the engine has, but I would guess a lot. I bought it cheap, having sat for years, and only drove it for about 20 miles before I broke the distributor trying to figure out why it seemed like it wasn't advancing/retarding under power. But it never ran well in the time I had it running. It has seen a lot of neglect, but mostly from sitting, rather than harsh use.

When I say, "cheapest" way to fix, I actually meant that I don't have thousands of dollars to take it somewhere for a rebuild. Since the head is off, & I don't know much about it, I was going to take it down to Gunn Automotive this week & have them clean it & magnaflux, etc... Am I wrong to assume that they will do the valves on all if i tell them to, "rebuild" the head, or do I need to specify that sort of stuff?

When the time comes, does anyone in the Boulder area have a Tap I could borrow for the head bolt holes & maybe also the Oil Galley Plug?

Randy - I assume that the rings are mediocre at the best, just based on how neglected everything is, but that is only a guess. I like the idea of new rings & fresh new compression, but pulling the head pretty much extends beyond my ability level, so the rings are not likely. Although I have been reading RcardoJM's f.5 rebuild thread, and the ring compressor doesn't look horribly complicated.

I'll go clean it up further & see what it looks like, now that it is light out & warming up. I'll let you guys know what it looks like when I get it cleaner.

Thanks!
Abe

Rzeppa
03-26-2012, 01:24 PM
It's best to chase the head bolt holes with a tap before reassembly.

When I was picking up my block at the machine shop the other day they apologized for not chasing the head bolt threads, explaining that they are an oddball 17mm pitch and they do not own a tap that size.

If an engine shop doesn't have one, they are probably pretty hard to find, and likely pretty darn expensive...

Rzeppa
03-26-2012, 01:30 PM
Abe, I would certainly check the head for flatness. While the F heads are not nearly as prone to cracking as the later 2F heads, it is certainly possible. I tend to agree with Bruce, clean it up as best you can then do as much inspection as you can, try to find to cause of the leak. If you can't find the cause, you could be wasting a lot of time by not fixing the right thing.

I like to use a wirewheel on an air powered die grinder to clean up rust, carbon and old bits of gasket. You can also use an electric drill but it takes longer. Scotchbright by hand takes even longer still. Whatever you do, make sure you plug off the holes where the pushrods go so you don't get too much crud down in the oil.

Air Randy
03-26-2012, 01:49 PM
Thanks for the ideas guys!

The head gasket itself doesn't have any paper on it now. Is it possible I, "scrubbed" it off when I hit it with the pressur washer @ the coin op place?

I have no idea how many miles the engine has, but I would guess a lot. I bought it cheap, having sat for years, and only drove it for about 20 miles before I broke the distributor trying to figure out why it seemed like it wasn't advancing/retarding under power. But it never ran well in the time I had it running. It has seen a lot of neglect, but mostly from sitting, rather than harsh use.

When I say, "cheapest" way to fix, I actually meant that I don't have thousands of dollars to take it somewhere for a rebuild. Since the head is off, & I don't know much about it, I was going to take it down to Gunn Automotive this week & have them clean it & magnaflux, etc... Am I wrong to assume that they will do the valves on all if i tell them to, "rebuild" the head, or do I need to specify that sort of stuff?

When the time comes, does anyone in the Boulder area have a Tap I could borrow for the head bolt holes & maybe also the Oil Galley Plug?

Randy - I assume that the rings are mediocre at the best, just based on how neglected everything is, but that is only a guess. I like the idea of new rings & fresh new compression, but pulling the head pretty much extends beyond my ability level, so the rings are not likely. Although I have been reading RcardoJM's f.5 rebuild thread, and the ring compressor doesn't look horribly complicated.

I'll go clean it up further & see what it looks like, now that it is light out & warming up. I'll let you guys know what it looks like when I get it cleaner.

Thanks!
Abe

If you tell Gunn to rebuild the head they will check it for cracks first, then do the valves and resurface it to ensure it is flat. If you ask them, they will also do the oil galley plug for like $5.

Now that you have the head and valves off, you've done all the really hard stuff. If you want to install new rings just drop the oil pan. Take one connecting rod cap off and push the piston up and out of the cylinder. Rent a cylinder hone at one of the parts stores, hone the cylinder, install the new rings on the piston, compress them (another rental tool), squit some oil in the cylinder and gently insert the piston. Put the new bearings on the connecting rod, bolt and torque the cap, now do the other 5 pistons one at a time. Just make sure you put the piston back in facing the same direction it came out. Very easy to do. Not as good a true full rebuild but will add some life to the motor for very little money.

A lot of times when you do a valve job on an old engine (where the valves may not have been sealing perfectly for some time) you raise the compression in the cylinder. That can make the old piston rings die quickly if they are close to the end anyways. Thus the logic for sticking a set of rings in as a safety measure.

subzali
03-26-2012, 03:19 PM
When I was picking up my block at the machine shop the other day they apologized for not chasing the head bolt threads, explaining that they are an oddball 17mm pitch and they do not own a tap that size.

If an engine shop doesn't have one, they are probably pretty hard to find, and likely pretty darn expensive...

I think you're right :(

I didn't chase mine and it seems to be fine. I also didn't replace the rings and they seem to be ok for now. Gunn will lap the valves and if any need to be replaced they will tell you. I think one of mine needed to be replaced, and they replaced all of my springs too.

rover67
03-26-2012, 06:11 PM
When I was picking up my block at the machine shop the other day they apologized for not chasing the head bolt threads, explaining that they are an oddball 17mm pitch and they do not own a tap that size.

If an engine shop doesn't have one, they are probably pretty hard to find, and likely pretty darn expensive...

I have one if you need to borrow it.

:D

wesintl
03-26-2012, 06:59 PM
maybe rising sun should donate them a 17mm tap :D

gr8fulabe
03-27-2012, 08:53 PM
If you tell Gunn to rebuild the head they will check it for cracks first, then do the valves and resurface it to ensure it is flat. If you ask them, they will also do the oil galley plug for like $5.

Now that you have the head and valves off, you've done all the really hard stuff. If you want to install new rings just drop the oil pan. Take one connecting rod cap off and push the piston up and out of the cylinder. Rent a cylinder hone at one of the parts stores, hone the cylinder, install the new rings on the piston, compress them (another rental tool), squit some oil in the cylinder and gently insert the piston. Put the new bearings on the connecting rod, bolt and torque the cap, now do the other 5 pistons one at a time. Just make sure you put the piston back in facing the same direction it came out. Very easy to do. Not as good a true full rebuild but will add some life to the motor for very little money.

A lot of times when you do a valve job on an old engine (where the valves may not have been sealing perfectly for some time) you raise the compression in the cylinder. That can make the old piston rings die quickly if they are close to the end anyways. Thus the logic for sticking a set of rings in as a safety measure.

Hi Randy,

The head is at the shop as of this afternoon (Mile High Performance instead of Gunn). How hard is it to pull the oil pan & replace with the engine still in the truck? It seems like it would be super difficult, and horrible to do it poorly.
Interesting to hear that you pull the piston out of the top. I was imagining that it would come out of the bottom for some reason. I really like the idea of doing the rings, but I'm just not sure if trying is a good idea.
1. Do you think it can be done by me & my wife (I've got few skills & she has none really, but likes to help anyway) in a day, or weekend at the most, with only hand tools, outside?
2. Do you have any guesstimate of what it would cost? Also, if it helps I do have a small portable air compressor & an air wrench to help with turning bolts in tight spaces, but it is too small for big tools.
3. Any idea if anyone sells a complete kit for this type of thing, or do you have to know what to order?
4. Does it make sense to buy Harbor Frieght tools (hone & Compressor) instead of renting? They are cheap, but it isn't like I would be using them all the time.

thanks in advance for any advice!
Best,
Abe

Rzeppa
03-28-2012, 12:46 PM
Hi Randy,

The head is at the shop as of this afternoon (Mile High Performance instead of Gunn). How hard is it to pull the oil pan & replace with the engine still in the truck? It seems like it would be super difficult, and horrible to do it poorly.
Interesting to hear that you pull the piston out of the top. I was imagining that it would come out of the bottom for some reason. I really like the idea of doing the rings, but I'm just not sure if trying is a good idea.
1. Do you think it can be done by me & my wife (I've got few skills & she has none really, but likes to help anyway) in a day, or weekend at the most, with only hand tools, outside?
2. Do you have any guesstimate of what it would cost? Also, if it helps I do have a small portable air compressor & an air wrench to help with turning bolts in tight spaces, but it is too small for big tools.
3. Any idea if anyone sells a complete kit for this type of thing, or do you have to know what to order?
4. Does it make sense to buy Harbor Frieght tools (hone & Compressor) instead of renting? They are cheap, but it isn't like I would be using them all the time.

thanks in advance for any advice!
Best,
Abe

I'm not Randy, but I can answer.

Pulling the pan can be easier sometimes while the engine is in the truck. How stuck it is on depends on how long it has been on there. When I did my daughter's 60 about a year ago it was a bugger because it had never been off ever I think. I did mine recently and it was super easy, my engine was rebuilt probably less than 10 years ago.

I have re-rung engines without taking the engine out. It is not too hard. Cleaning the carbon out from the piston grooves can be work. Make sure you keep your rod caps with the rods and oriented! Also, make sure you stuff rags in the bottom of the cylinders when you hone so you don't get anything on the crank.

More answers:

1. Yes

2. I also had MHP do my machine work just now, including head, but they put chebbie valves in so it cost more than if they re-use your old valves, springs, and keepers. You should probably expect to pay $200-$300 for a standard head job. Mainly that will be for recutting valves and seats, checking springs and guide wear, checking flatness and redecking if necessary and inspecting for cracks. Might include magnaflux too, dunno. Your air ratchet will speed up some of the disassembly, there are (I think) 22 bolts that hold the pan on.

3. MHP can sell you the rings from their supplier, or you can order them from SOR. They aren't too expensive. You might consider replacing all the rod bearings while you're in there. Again you can get those through MHP or SOR. Also, not too costly. And you're in there anyway.

4. Hones and ring compressors are not costly (maybe $10 or so?) and you can usually get them at any parts store in addition to Tool King and HF. I haven't really seen much difference in quality from one hone or compressor to the next. Of course you are welcome to borrow mine.

rover67
03-28-2012, 01:01 PM
When I hone cylinders, I like to take electrical tape and put it around the rod journals on the crank to keep crap out of the little oil hole in them to. Make sure you wash all the crap out of there when you're done. I use brake cleaner or something.

if you pull the rods out of it just try to be super clean. any crap that gets in between the rod bearings and the journals (or mains/journals for that matter) will ruin a good set of bearings. Also, make sure you are careful when you replace those bearings.. the little tangs that hold them in place can get bent and bind things up. Just make sure they are popped into their places nicely before putting the caps on and tightening it all down.

Like Jeff said, keep the rod caps with their respective rods and oriented right. keep the bearings in the same spots if you are reusing them too. don't do it outside if it's windy.. you gotta keep it all CLEAN.

Air Randy
03-28-2012, 01:57 PM
All good answers. I think you were asking about the estimated cost though to do the re-ring job versus the head rebuild. I think the last set of rod bearings I bought was $35 and a decent set of piston rings was like $60, plus you will need an oil pan gasket for $10.

If you go to AutoZone you will need to get: A ridge reamer to remove the ridge that builds up at the very top of each cylinder so the pistons can pop out without cracking a piston; a cylinder hone; a piston ring groove cleaner; a piston ring compressor and a torque wrench. You can "buy" those from Autozone then bring them back for 100% refund when you're done, thats how they operate their tool rental program. I also have all of those tools if you want to borrow them.

If you schedule it in advance I'm sure myself, Ricardo and probably others would be glad to give you a hand. Once you have the oil pan off, and if you have the tools above in hand, we can easily complete the re-ring process in 4 hours.

If the vehicle is easy to move, we could even winch it up onto my car trailer and bring it down to my shop to put everything back together. That way we have plenty of room and all the tools required to deal with any issues that may arise.

gr8fulabe
04-01-2012, 10:42 PM
Hey guys,
Sorry to let this drop for a few days. i got stuck doing some minor stuff on my troopy, which turned into much longer, slower projects than I thought.

Randy, if you or someone else is willing to help me out to make sure this job goes right, I'd be more than grateful. I'd be willing to fire up the grill & keep the cooler stocked with beer to make it a great day. I'd also be willing to be an extra set of hands to help on your projects as well. Sometimes extra hands rock! Also, if you were willing to use your shop/trailer, I could tow the truck to the bottom of Magnolia road in Boulder Canyon, which has a big parking lot & would be easy to load it up. It is easily snagged where it sits, but I wouldn't want to trailer it down magnolia. But I could strap it to the road & roll/break it down the hill. I could be free just about any weekend, or even a weekday if it was best. Just let me know what timing would work for anyone else.
So parts-wise at this point I think I need":
1. Head gasket
2. intake/exhaust gasket
3. Valve Cover gasket & new nuts/seals I think
4. Thermostat gasket
5. ???? other head job gaskets?
6. Ridge Reamer/hone/ring compressor thing
7. rod bearings
8. piston rings
9. rags/cleaners/some sort of assembly lube
10. Oil Pan Gasket
11. Rod bearings? Rod Caps (or are they re-usable)?
12. should I go all oem or does it not matter for this type of work?
13. oil/fluides

Anything else? I think that sounds like the full list, but that is just compiling from your guys' posts above.

thansk,
Abe

RicardoJM
04-02-2012, 09:29 AM
....
So parts-wise at this point I think I need":
...
5. ???? other head job gaskets?
...
7. rod bearings
8. piston rings
...
11. Rod bearings? Rod Caps (or are they re-usable)?
...
Anything else? ...

You probably need a side cover gasket as well. Regarding the rod bearings and rings, size matters. When you go to by the bearings and rings, the supplier will need to know if you need standard or oversize; and if oversize how much oversized. If you do not know the history of the engine, you should determine the apporpriate size to avoid getting the wrong parts. Do you know if the engine has ever been worked on before?

Your rod caps should be re-usable.

Air Randy
04-02-2012, 10:03 AM
Good point, if the engine has been rebuilt/bored out before now then the piston rings could be .010 over sized already.

Do you have access to an ID caliper to measure your cylinder bore? Maybe Marco or someone out in Boulder could help you with that. That way you can be sure. Also, when the time comes to buy piston rings, get the better quality ones. One of the big differences is, the cheaper ones require you to align the ends of the oil wiper ring very precisely. It is very easy to accidentally overlap the end of this ring which will hurt your compression slightly and not get as good of an oil seal. The better quality rings come with a little pin & hole on the ends of the ring so the pin goes into the hole and makes it impossible to overlap the ends. I forget which brand those are but I know Sasch/Nattybumpo got that style when he bought his parts from Gunn Automotive.

If you get the better quality stuff from Gunn, IMHO, you can save a bunch of money versus buying OEM and it should work just fine. I've never bought OEM gaskets or parts (rings/bearings, etc) for any of the F/2F's I've worked on and so far have not had any issues (knock on wood).

Getting a side cover gasket is not mandatory since you don't have to remove that cover for this project. However, sometimes in the process of cleaning off head gasket crud, some of it falls down into the lifter galley. If you have the time, it's not a bad idea to pull it so you can clean that area out good.

I didn't pull mine off when I did the shade tree rebuild on my first F motor. Later, we replaced the cam and lifter and pulled that cover. The entire lifter galley was filled with what looked like oily charcoal. Literally, we had to crack it with a screw driver and pry the chunks out. It's amazing that any oil got down in there where it was needed. The previous owner probably never changed the oil and ran a super dirty air filter for this crap to build up like that.

If you are in a hurry we will have to do it at your place. My shop is booked this weekend for Easter and work on the race car, the following weekend is the next pre-Moab wrenching weekend and then I have to get my rig ready for Moab.

gr8fulabe
04-02-2012, 10:29 PM
Hi guys,
Thanks for the responses. No rush on the timing. This could easily be after Moab. I haven't even heard if the head is okay yet, let alone gotten a timeline for when it will be done (I told him no rush, if any priority biz came up).

I can definitely get the better quality parts, that's for sure! If i can't borrow an ID Caliper, I could possibly rent one from napa. Again, not a rush, as the job done right is better than a job done fast. I will say though, that I would love to not replace the side cover gasket becuase it has ZERO miles on it. I replace it when I did the dented side cover, and was working on the newer dizzy, that led to this job. So it is effectively brand new. but if I have to replace it, that is fine.

I guess I will just keep cleaning it up & etc.... & give you guys an update when I hear anythign from the shop. We can take it from there later...

thanks,
abe

Air Randy
04-03-2012, 10:40 AM
If you've already had it off and the lifter galley is clean you should be OK.

Rzeppa
04-03-2012, 02:47 PM
FWIW, "standard" over is in increments of 0.020" (0.5mm) for the cylinders. I think 0.060" is as far as they go before you have to sleeve it. I had two of mine sleeved.

gr8fulabe
05-22-2012, 09:53 PM
Hey all,

Bringing this old chestnut back up, I picked up my head from MHP right bfore Cruise Moab. I had them do the Chevy Valves & all of that good stuffn as well, so it is sweet & ready to go. I made a PDF scan of the receipt & was thinking i could post it up in this thread so that there is a record of what they do & what it costs, in case it could be helpful to future head gasket people. BUT, I didn't ask for permission. I would think it is only good advertising for MHP, but who knows. What do you guys think? Is it okay to post a copy of my receipt or should I skip it? If yes, how do I post a PDF?

I still haven't measured the pistons or anything to figure out what ring size I need, nor have I ordered the gasket set yet, so it isn't quite ready to go. But getting closer all the time! Plus, the head looks spectacular!

Best,

Abe

Rzeppa
05-23-2012, 02:55 PM
Hey all,

Bringing this old chestnut back up, I picked up my head from MHP right bfore Cruise Moab. I had them do the Chevy Valves & all of that good stuffn as well, so it is sweet & ready to go. I made a PDF scan of the receipt & was thinking i could post it up in this thread so that there is a record of what they do & what it costs, in case it could be helpful to future head gasket people. BUT, I didn't ask for permission. I would think it is only good advertising for MHP, but who knows. What do you guys think? Is it okay to post a copy of my receipt or should I skip it? If yes, how do I post a PDF?

I still haven't measured the pistons or anything to figure out what ring size I need, nor have I ordered the gasket set yet, so it isn't quite ready to go. But getting closer all the time! Plus, the head looks spectacular!

Best,

Abe

They did a nice job on my head, too, chebbie valves just like they did for you. You can attach a PDF same as a picture, use the manage attachments function. There will be a size limit just like all the other file types.

gr8fulabe
05-30-2012, 10:05 PM
Invoicej from the Machine Shop. Hopefully this comes through as legible.

28919

Rzeppa
05-31-2012, 10:35 AM
That's pretty much exactly the same as what they did for mine. I see you got the same kind of discount they gave me, where they do a whole job they discount the individual line items.

I found out yesterday that Toyota no longer makes head gaskets for F engines, so it looks like I'll have to use the one that came in the kit from MHP. The box says ITM brand.

TIMZTOY
05-31-2012, 09:15 PM
(have not read all post, just first 3)
since you have the head off id take it into a machene shop to have it checked, thats pretty cheap.. and alot better than wasting time and money guessing

and if there is any pitting under the rust spots on the block, it will need to be resurfaced either boared over for the cylinder walls, and or decked for the head surface. other wise if no pitting, just hone it out and go. I would always have the head resurfaced regaurdless becuaue they tend to warp alot eaiser that the blocks. expectually if the motor is cast block, aluminum head.