How does it look?, The damage to cylinder 2 more pics added Options

[nditiz1]

Ok so here are some pics of the dropped valve on cylinder 2. A quick recap, I was installing a new dist., loud back fire, no crank as it was stuck, free motion limited, scoped and found dropped valve. The questions I have for the experts:

1. How bad is the damage to the piston?
2. I am replacing the heads with new heads from HAM built on AA heads, should I replace the jugs and pistons? If so, which ones, as I read don't get Keith Black, something like that...
3. If I am already here and don't know the true inner workings, should I tackle the whole engine as a rebuild, mind you money is tight with having to drop $1400 on new heads. If new cyl and pistons are needed thats another hit. I guess bearings and seals are not much more. Don't think I would need to mess with the crank and rods?

Pics:

[white1975]

you got lucky

heads aren't sealing bottoming out on cylinder

looks like they were fly cut

[yeahmag]

How many miles are on the motor?

I'd suggest at a minimum, pulling the P&C and taking them to the machine shop to get the cylinders honed, checked for roundness, and new rings on the pistons. It's really not much more to get new P&C's, but you still need to check those as well.

As far as the bottom end is concerned, at the minimum I'd suggest removing the rods (which you can do without splitting the case) and having them checked for straightness and replace the bearings.

As was previously pointed out, you weren't sealing correctly on the cylinder-head interface. Make sure to check for that with the new combo.

[crash914]

you are local to me. I am in Marriottsville, by liberty res.

I have a core motor, extra P/C for stock and a set of NOS Biral's if you want to go larger!

I also have several sets of heads..When my motor went up, it was much worse than what you show. I had a new set of LE heads so welded them up and had Baltimore headworks and Ladd's head porting work on them.

Give me a call or swing by anytime (evening) I can pull out what I have. 410 five 9ine 6ix- 5ive 880. House/shop is on Wards Chapel rd. South of liberty road.

[wndsrfr]

How many miles are on the motor?

I'd suggest at a minimum, pulling the P&C and taking them to the machine shop to get the cylinders honed, checked for roundness, and new rings on the pistons. It's really not much more to get new P&C's, but you still need to check those as well.

As far as the bottom end is concerned, at the minimum I'd suggest removing the rods (which you can do without splitting the case) and having them checked for straightness and replace the bearings.

As was previously pointed out, you weren't sealing correctly on the cylinder-head interface. Make sure to check for that with the new combo.

Deck the case......Can't get a proper seal without that.

[McMark]

WHOA!!!!

Somebody f-ed up your engine on a previous 'rebuild'. (IMG:style_emoticons/default/yikes.gif) (IMG:style_emoticons/default/barf.gif)

Your heads were not sealed to the cylinders. This means that combustion was leaking by and so you're losing power there. On a long trip this could have turned into a hole in the head, burned away from hot escaping gasses.

In your pictures you can see that the heads were sealing against the FINS of the cylinder, and NOT on the main bore of the cylinder. Where I've noted 'Clean' is clean because there was contact. Where I've noted 'Dirty' is where there SHOULD be contact be obviously is none.

This little frustrating problem just turned into a lucky break. You just saved yourself from a lot more damage.

[nditiz1]

WHOA!!!!

Somebody f-ed up your engine on a previous 'rebuild'. (IMG:style_emoticons/default/yikes.gif) (IMG:style_emoticons/default/barf.gif)

Your heads were not sealed to the cylinders. This means that combustion was leaking by and so you're losing power there. On a long trip this could have turned into a hole in the head, burned away from hot escaping gasses.

In your pictures you can see that the heads were sealing against the FINS of the cylinder, and NOT on the main bore of the cylinder. Where I've noted 'Clean' is clean because there was contact. Where I've noted 'Dirty' is where there SHOULD be contact be obviously is none.

This little frustrating problem just turned into a lucky break. You just saved yourself from a lot more damage.

Thanks a lot Mark! You guys are great at showing me the unknown. I could never have known all that is going on just by the pictures. (IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/pray.gif)

Ok with the new info coming in, sounds like I should do a proper full rebuild. Good thing I own Raby's Bug Me video on the type 4 rebuild.

What I am looking at cost wise? I don't even know where to begin (i.e. sending out the case, rods, crank, buying new bearings, seals, P&C) this is not going to be cheap (IMG:style_emoticons/default/sad.gif)

[McMark]

So new heads will basically fix all your problems.

If you can swing it, I would add a set of 96mm pistons and cylinders to the order. EDIT: actually the leaking combustion may have distorted or eroded the cylinder sealing surface. I'd strongly recommend replacement.

You'd be well set to install new P&C and new heads and be back on the road. You don't need to check deck height (although I'd strongly encourage it). You don't need to change to custom length pushrods (I wouldn't encourage it in this instance).

If you want to go one step farther, you can remove the connecting rods without splitting the case. Get those rebuilt and install with new rod bearings. You'd need a 14mm socket with a magnet inside (so you don't drop a rod nut into the bottom of the case). You'll need a torque wrench to reinstall the rods.

And regardless of either of those, I would pull the oil pump so you can 1) reseal it to the case with Loctite 518 to avoid leaks and 2) look at the end of the camshaft to see if there are any numbers (post pictures).

There's always more you can do 'while you're in there'... Spend as much as you can handle, because it's an investment in not having to dig back in.

And finally, clean, clean, clean, clean, clean, clean. Two reasons to spend a lot of time cleaning your engine right now. First, any sealing surfaces MUST be clean to seal. So if you don't replace those pistons and cylinders, the sealing surface must be cleaned of all that carbon build up. But besides sealing surfaces, I find that taking time to meticulously clean things gives me lots of eyeball time on that part/assembly. So naturally, if there's a little ding or dent or crack or bend or anything else, you have a greater chance of noticing it if you're spending time scrubbing away with your eyes glued to the part. I can't tell you how many times this has saved my ass from something I hadn't noticed before.

Oh and one last section here. Definitely replace the front and read main seals. I can loan out my factory seal install tools, PM me for details.

[Mark Henry]

Just asking did the engine squeak like it had a mouse squeaky toy stuck in it?
Likely most prevalent at low RPM, light or no load.

[nditiz1]

Just asking did the engine squeak like it had a mouse squeaky toy stuck in it?
Likely most prevalent at low RPM, light or no load.

I didn't notice it, but I did notice that it didn't seem to have the power it should. I kept going through carb tuning trying to figure it out. I guess my issues stemmed lower. Yay for unknown builds (IMG:style_emoticons/default/slap.gif)

Will dig in more tonight and post pics so you all can tell me what else is Fubar

[nditiz1]

Ok more pics of the dropped valve from Cyl 2 and the head from 3/4 side. Is this the stock oil pump plate as it is stamped USA?Opened the oil pump up to check the unknown cam, but don't see any markings besides the "0" "2" nothing on the cam gear itself. I turned it all the way around looking. Anyone know? Also, one of the push rods has a perfect wear mark around it. Should I be concerned with something else? This came off the 3/4 side.

Pics:

[bbrock]

Oil pump is not stock. Looks like it might be a Melling which are junk from what I've read. I made the mistake of buying one for my build back in the day but am not going to use it.

[Valy]

I would just remove pistons and cylinders, clean and check them out.
If everything checks out good, replace rings and put the new heads on. Rings are cheap and are the minimum I would do while in there.

The pushrod scratch is from the retaining wire. It doesn't look too bad, I would reuse it but if you want to replace, there are plenty of good used ones around.

Good luck.

[nditiz1]

Ordered new P&C.

Anyone know which oil pump I should replace this USA one with? What can I look at on the pump itself to decipher?

[yeahmag]

I’ve always had good luck with CB performances pumps. I do always go through them very thoroughly just to make sure though.

[McMark]

Those pistons looks like they have zero deck height (the piston top is flush with the cylinder top at TDC). Check the stroke of the crank by measuring the distance from the top of the cylinder to the top of the piston at BDC.

You may have a clearance issue with a Schedek pump (and possibly others) and those cam bolts. The bolts can be swapped without splitting the case.

[VaccaRabite]

Those pistons looks like they have zero deck height (the piston top is flush with the cylinder top at TDC). Check the stroke of the crank by measuring the distance from the top of the cylinder to the top of the piston at BDC.

The deck height was built in by not setting the heads to the cylinders. It was planned. The builder thought of EVERYTHING!

(IMG:style_emoticons/default/piratenanner.gif)

Zach

[nditiz1]

Those pistons looks like they have zero deck height (the piston top is flush with the cylinder top at TDC). Check the stroke of the crank by measuring the distance from the top of the cylinder to the top of the piston at BDC.

You may have a clearance issue with a Schedek pump (and possibly others) and those cam bolts. The bolts can be swapped without splitting the case.

Mark,

Looks like the pump is a selling. The numbers lined up with your chart in another post. That and the usa 8mm. Is melling an ok pump?

I checked the stroke at bdc. Looks to be 71 so at least i know a stock crank.

Zach - (IMG:style_emoticons/default/lol-2.gif)

Edit - deck height with feeler looks to be .011 - I read .045 is good, confirm?

[MarkV]

You will need something like this:

http://vwparts.aircooled.net/Cylinder-Base...-base-shims.htm

[nditiz1]

You will need something like this:

http://vwparts.aircooled.net/Cylinder-Base...-base-shims.htm

Ok that will help set the correct height, now the big mystery is how do I know if my compression ratio will match my carb cam if I don't know my carb cam.

I can measure cam lift right?

Since the heads will be new non fly cut I should be good with .040 on the new p&c