Looking for advice on an Atomic 4 repair / replacement

[ndutton]

I'm talking to a guy who recommends turning over the A4 to find TDC by clicking it over with the starter motor. Not manually cranking it at the flywheel or prop shaft.

Stop talking to that guy, he's an idiot. On the other hand, maybe go ahead and try it his way. You'll come to the same conclusion on your own. With my home made balloon indicator I can find #1 TDC in about 30 seconds and that includes the engine in the boat.

[infy]

Stop talking to that guy, he's an idiot. On the other hand, maybe go ahead and try it his way. You'll come to the same conclusion on your own. With my home made balloon indicator I can find #1 TDC in about 30 seconds and that includes the engine in the boat.

Pretty smart trick with the balloon. I don't have compression since the head is off.. in fact, I have no compression with in on either

So I'm just looking to get No.1, No.2, etc to TDC so I can adjust valve clearances on each on the compression stroke.

I plan to replace all 8 valves and guides this weekend. Then set the clearances, install a new head gasket, and cross my fingers.

I wish I had access to a dial bore gauge so I could check for roundness, taper, and bore on the cylinders while I have access to them. The tool is $200.... and I'm not going to need it again for a long time

[Al Schober]

While you have the head off, make sure those cooling passages in the block (between the valves and the edge of the block) are clear. They go straight down a short way, then take a turn fwd or aft to clear the intake & exhaust passages.
Chipping at them with a small screwdriver and hammer works well, but wear eye protection with side shields. Visits to an ophthalmic surgeon are no fun.

[ndutton]

Pretty smart trick with the balloon. I don't have compression since the head is off. . . . so I'm just looking to get No.1, No.2, etc to TDC so I can adjust valve clearances on each on the compression stroke.

Even easier with the head off. TDC is a precise setting, the reason I think using the starter is a no-go.

Are you resisting cutting the flywheel access hole for some reason?

[infy]

Even easier with the head off. TDC is a precise setting, the reason I think using the starter is a no-go.

Are you resisting cutting the flywheel access hole for some reason?

Not really, I don't mind doing a useful modification. One day the engine may need to be started without power. That's an awesome feature to have. I'm probably going to buy the official crank from MM.

So I'm at home poking at this second engine I bought... I mentioned that it made a mess of oil as soon as I set it down. We concluded it's coming from the flywheel area where there is no oil seal... more specifically, the oil I saw come out appeared to have leaked from here:

What exactly is this? It looks like there's a missing bolt? Do I need to plug this? If there's a part here, I could probably take it off the other A4.



Here's some more dirty A4 imagery attached

[lat 64]

Pretty smart trick with the balloon. I don't have compression since the head is off.. in fact, I have no compression with in on either

So I'm just looking to get No.1, No.2, etc to TDC so I can adjust valve clearances on each on the compression stroke.

I plan to replace all 8 valves and guides this weekend. Then set the clearances, install a new head gasket, and cross my fingers.

I wish I had access to a dial bore gauge so I could check for roundness, taper, and bore on the cylinders while I have access to them. The tool is $200.... and I'm not going to need it again for a long time

This is a job that is done in preparation to a full valve seat grind. You will not get satisfactory results.Your valves are most likely fine, as well the cylinder bore. You are confusing us with all this talk about some basic engine diagnostics mixed with advanced engine machine work techniques. Most of which is unessesary for this resurrection. Measuring an engine for a rebuild is an art more than a science and cannot be learned from youtube.

These A-4 don't wear out, they just go bad from sitting around and getting rusty and stuck valves. work things loose, lube it up, and put it back together.
You are getting advice on this forum from probably the best source, and if we go wrong, Don Moyers and Co. would set us straight and you on the right path.

[ndutton]

So I'm at home poking at this second engine I bought... I mentioned that it made a mess of oil as soon as I set it down. We concluded it's coming from the flywheel area where there is no oil seal... more specifically, the oil I saw come out appeared to have leaked from here:

What exactly is this? It looks like there's a missing bolt? Do I need to plug this? If there's a part here, I could probably take it off the other A4.

That is a drain hole in the flywheel housing. Don't put a bolt in it.

[infy]

That is a drain hole in the flywheel housing. Don't put a bolt in it.

Thanks!! That's why I'm here.. you guys know this motor better than most mechanics.

Ok I finally have the long awaited valve video. Not from the valve cover.. I need to get a wire with a switch I can hold... but here it is from the top:

[YOUTUBE]https://youtu.be/hYbFZg-5-Qg[/YOUTUBE]

The YouTube embed tag doesn't seem to work... direct link

https://youtu.be/hYbFZg-5-Qg

[ndutton]

Nice video but a feeler gauge is the acid test. It's also entirely possible that the simple act of turning the engine over could free up sticky valves too.

[Peter]

It appears to me from the video that #1 exhaust is not closing fully and, if I recall your very first post correctly, that was the cylinder with zero compression.

As Neil has noted, the feeler guages are "the definitive" answer.

You could also probably get a good sense from examining the valve seats when the valves are fully open.

Peter

[roadnsky]

There's a good post HERE about valve adjustment and such.
Rigs made a good drawing and some pics too.

[infy]

Looks like most of my valve keepers are jammed to the retainer tried pressure. Tried tapping on the valve head with the rubber back of a screw driver... haven't got the hammer out yet don't worry. Any ideas?

[ndutton]

What are you using for a spring compressor?

[infy]

What are you using for a spring compressor?

Fork pulling up to the engine deck. I wonder if the fork is skewed..

I'm doing some feeler measurements on the cylinder head.. specs show .006 is acceptable. I meet that. But a .004 feeler will just barely slide through to the center. Going to see if I can get a quote from a machine shop tomorrow to do the flat head. If the price is reasonable I may go for it.

If I can't justify it with a good $400 engine sitting in my garage I may consider swapping the heads.

Or leave it as-is.. throw head gaskets on and check if I get compression back. If the book says .006 is ok I may just take their word.

[joe_db]

The head has nothing to do with the valves sticking. I am not sure I get the connection