72maverick
Well-known member
My neighbor is convinced its the head bolts still
still smoking..
- Thread starter 72maverick
- Start date
72maverick":cmfyiowp said:
I'm a little confused. You say you hadn't see "it" since, but then mention you "could see green bubbles coming from the crack " (assuming you mean coming from the seam where the head meets the block
: Please clarify if I'm wrong it will help us provide diagnosis advice.Assuming the "green bubbles" are coming from the seam between the head and the block (head gasket area), I'd want to make sure none of the heads freeze plugs are leaking (doubtful if you're seeing the bubbles at the seam, but easy enough to check). Head freeze plugs are all on the passenger side just above this seam. Little hard to see from above cause they're below the log, but easy enough to visually inspect from below with a mirror & flashlight to look for coolant/green residue around the head freeze plugs.
Best guess at this point is your buddy may be right. One thing often missed in these situations is chasing the head bolt threads/holes in the block with a bottom tap and then blowing them out with compressed air. The bottoms of the head bolt holes can get filled with dirt, rust etc and give false torque readings. You'll get to the max ft/lb reading but it could be based on the bolt bottoming out, not the same as the clamping force of the head to the block.
The impeller and pump are on the small side and unlikely to create bubbles. More likely is you've got slight compression leak forcing the coolant out. You should also check the smoothness across the block and head gasket surfaces using a known good straight edge like a 2ft metal level. If your using something like a felpro head gasket it will be forgiving for minor imperfections in the eveness of the surfaces. My guess is a bottom tap needs to be chased into the head bolt holes (or replacing with studs is another option). Good luck
EDIT: [sidebar musing:] anyone know why typing is such a chore 100-200 words into a post...it's like my anemic typing is outpacing the GUI
72maverick
Well-known member
Guess I hadn't noticed the leak until recently. It is between the head the the block. I watched as it bubbled from the seam
That's one reason I like the Felpro's and asked what type you used. They lower compression with their thickness, but they sure do seal great, out of the package (no additional RTV or other gasket sealing glues required).
My advice. Change the head gasket...probably not what you want to hear if you're on your second one already, and never reuse a modern head gasket. Check the surfaces for straight/trueness and chase the bolt holes in the block with a bottom tap. Test run all your bolts to make sure they'll drop in far enough (i.e. leaving less than the thickness of the gasket surface on the bottom of the head to the head bolt seats up top, aka thickness of the head...calipers may come in handy for measuring). Hopefully will resolve the leak and the weak compression, and I assume you've got no 'milk shake' in the oil Good luck
My advice. Change the head gasket...probably not what you want to hear if you're on your second one already, and never reuse a modern head gasket. Check the surfaces for straight/trueness and chase the bolt holes in the block with a bottom tap. Test run all your bolts to make sure they'll drop in far enough (i.e. leaving less than the thickness of the gasket surface on the bottom of the head to the head bolt seats up top, aka thickness of the head...calipers may come in handy for measuring). Hopefully will resolve the leak and the weak compression, and I assume you've got no 'milk shake' in the oil
Good luck 72maverick
Well-known member
Haven't seen the milkshake. And it is felpro I believe. The whole permatorque thing. I guess I should try the arp studs since im in there
EDIT: Well studs have some nice benefits, better and more accurate overall clamping force, not inclined to 'stretching', and make it easier to locate the gasket and head during assembly. However, if cost is a concern, Mike@Classic Inlines has very reasonable price on both a Corteco Head Gasket with Permatorque and a thinner 'crush thickness' to keep compression up, and really nice dual metal faced exhaust header/manifold gasket, since you don't need a full 'head set' gasket set with your weber carb (Tstat housing gasket is over the counter at Autozoo) that could save you some money towards the studs (which CI also carries...check with Mike/AzCoupe for availability).
They do seal nicely with just the right about of sticky stuff in the right places, and I meant no offense to bubba in regards to using a sealant to stop a head gasket leak. I'm not too shy about stating my opinion, but do not intend for it to come across as crass...just figure that's what these forums are all about, learning about different approaches. If this was a high mileage engine that you were wanting to limp along until a rebuild that would be horse of a different color. Figure in for a penny in for a pound...you'll be better off with a new head gasket and verifying surfaces are flat planes, and if it's not a DD and you can afford to park it a bit longer, might as well fix it and be done [crossing fingers]
Good luck
72maverick":gvtp92ok said:
They do seal nicely with just the right about of sticky stuff in the right places, and I meant no offense to bubba in regards to using a sealant to stop a head gasket leak. I'm not too shy about stating my opinion, but do not intend for it to come across as crass...just figure that's what these forums are all about, learning about different approaches. If this was a high mileage engine that you were wanting to limp along until a rebuild that would be horse of a different color. Figure in for a penny in for a pound...you'll be better off with a new head gasket and verifying surfaces are flat planes, and if it's not a DD and you can afford to park it a bit longer, might as well fix it and be done [crossing fingers]
Good luck
72maverick
Well-known member
I'll try these. I also got a lead on a trans and a running engine for cheap and a free running engine else where and a spare block and head. So thankfully there's other options worst case
72maverick
Well-known member
But willing to try the head gasket again and hopefully that's that. Although a 250 would be nice
If you have already pulled the head a couple times or tired a couple different heads and still have the smoking. Then
I think you might be better off pulling the engine out and checking the block out i.e. the pistons, ring gap etc. and cylinder walls or swap in a known good engine until you can fix yours.
I think you might be better off pulling the engine out and checking the block out i.e. the pistons, ring gap etc. and cylinder walls or swap in a known good engine until you can fix yours.
72maverick
Well-known member
Thinking of doing that if it leaks once more
72maverick
Well-known member
If I go with the 250 will the transmission bolt up to it?
Yes thought it Depends on the trans you are using, but for sure you will need to change the bell housing and flywheel maybe also the starter. Good luck
Edit with a C4 it is easy you would only need to change the bolt on bell housing to a 6 bolt from a 250 or 302 V8 and also the 250 flex plate and torque converter.
Edit with a C4 it is easy you would only need to change the bolt on bell housing to a 6 bolt from a 250 or 302 V8 and also the 250 flex plate and torque converter.
if it's a '72/4 Mav. it doesn't have the 3.03 transmission does it? A "3-on-the-tree"? That's good to 500 hp. It bolts up (came OE) to my 170...
Is it a C4? that auto will go on the 250 easy.
I like ur idea of one more try better, tho.
Is it a C4? that auto will go on the 250 easy.
I like ur idea of one more try better, tho.
72maverick
Well-known member
Its a c4 trans. I think I'll try some head bolts or studs and a new gasket
72maverick
Well-known member
Hello all,
Here's an update. I pulled the valve cover, no oil in water and no water in the oil. All the valve seals were installed and new. A few of the head bolts had some play in them so I'm leaning towards the it being old head bolts. Ordered that and a new head gasket and hopefully will install them soon
Here's an update. I pulled the valve cover, no oil in water and no water in the oil. All the valve seals were installed and new. A few of the head bolts had some play in them so I'm leaning towards the it being old head bolts. Ordered that and a new head gasket and hopefully will install them soon
72maverick
Well-known member
So after changing out the pcv, the smoking at idle is less. Still present but not nearly as bad. Still smokes under acceleration. Haven't seen any more leaks of coolant ever since I retightened the head bolts. So trying some ARP head studs (thanks to Mike for wonderful customer service) and new head gasket. While I'm in there I plan to check everything out see if everything is flat like it should be between the head and the block. Also drop in my adjustable rockers since the push rods are coming with the Head studs. Shoul be installed within the month. I'll post what happens..
Thanks Again
Thanks Again
72maverick
Well-known member
So after changing out the pcv, the smoking at idle is less. Still present but not nearly as bad. Still smokes under acceleration. Haven't seen any more leaks of coolant ever since I retightened the head bolts. So trying some ARP head studs (thanks to Mike for wonderful customer service) and new head gasket. While I'm in there I plan to check everything out see if everything is flat like it should be between the head and the block. Also drop in my adjustable rockers since the push rods are coming with the Head studs. Shoul be installed within the month. I'll post what happens..
Thanks Again
Thanks Again
Good deal Just make sure you chase the threads in the block with a bottoming tap...
Here's a good description of how these 3 types of taps work:
Principle features of taps are:
The most common hand taps are called taper, plug, and bottoming taps.
All three tools are identical except for the bevel angle at the tip. The bevel at the tip serves two purposes: it guides the tap into the hole and it ramp cuts the undeveloped first threads.
Taper taps have the longest bevel angle with 8 to 10 undeveloped threads.
Plug taps are the most popular of the three and have 3 to 5 undeveloped threads on the bevel.
Bottoming taps have only 1 to 1 1/2 undeveloped threads at the tip and should be used only when full amount of threads specified on the drawing can not be achieved by the other two taps.
The number of flutes and the geometry of the cutting edge will depend on the material tapped.
With the exception of the tip, the three hand taps will form thread to specifications and can be used independently.
The bottom tap should only chase the threads originally cut by the taper or plug tap (for hand tapping) The bottom tap is only forming the last few threads.
I highly recommend chasing all the holes in the block that receive the head bolts. Use a good 'cutting' oil be sure to blow out the holes with compressed air when finished so you can be sure nothing prevents the head bolts from threading all the way down.
To prep the gasket surface of the head and block (assuming you check them with a 'good' straight edge and they don't need re-surfacing)...I like this 3M product that can be used on a drill or die grinder (the yellow one). It's not aggressive enough to remeve any cast iron material, but will remove any rust, residual gasket material, crud caused by the leaking gasket, etc., and will ensure a good seal.
I believe you'll resolve more than one problem (leak & weak compression) with a thorough approach when installing your new head gasket. As the carpenters say, "measure twice...cut once". meaning take your time to get it right, and you won't have to revisit it. Good luck!
Just make sure you chase the threads in the block with a bottoming tap...
Here's a good description of how these 3 types of taps work:
Principle features of taps are:
The most common hand taps are called taper, plug, and bottoming taps.
All three tools are identical except for the bevel angle at the tip. The bevel at the tip serves two purposes: it guides the tap into the hole and it ramp cuts the undeveloped first threads.
Taper taps have the longest bevel angle with 8 to 10 undeveloped threads.
Plug taps are the most popular of the three and have 3 to 5 undeveloped threads on the bevel.
Bottoming taps have only 1 to 1 1/2 undeveloped threads at the tip and should be used only when full amount of threads specified on the drawing can not be achieved by the other two taps.
The number of flutes and the geometry of the cutting edge will depend on the material tapped.
With the exception of the tip, the three hand taps will form thread to specifications and can be used independently.
The bottom tap should only chase the threads originally cut by the taper or plug tap (for hand tapping) The bottom tap is only forming the last few threads.
I highly recommend chasing all the holes in the block that receive the head bolts. Use a good 'cutting' oil be sure to blow out the holes with compressed air when finished so you can be sure nothing prevents the head bolts from threading all the way down.
To prep the gasket surface of the head and block (assuming you check them with a 'good' straight edge and they don't need re-surfacing)...I like this 3M product that can be used on a drill or die grinder (the yellow one). It's not aggressive enough to remeve any cast iron material, but will remove any rust, residual gasket material, crud caused by the leaking gasket, etc., and will ensure a good seal.
I believe you'll resolve more than one problem (leak & weak compression) with a thorough approach when installing your new head gasket. As the carpenters say, "measure twice...cut once". meaning take your time to get it right, and you won't have to revisit it. Good luck!
72maverick
Well-known member
Thanks for the help and great explanations. The use of studs should help make sure alignment is good and I plan to chase all the bolt holes. A little extra insurance never hurt. I'll post some future updates.
