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Compression in my J13 engine


Rusty Dawg

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I shouda took more shots of the head when I rebuilt the E1. This is the best I could find of the combustion chamber & valves/seats right after I lapped them in after grind. Guides & valves were all new. 

 

Valve-Seats-Lapped.jpg

 

I'm freshening up my 1600cc VW for the 1964 Bug right now and it has 12K-15K on new heads that was rebuilt 18 years ago. I'll lap the valves and see how they turn out. 

Edited by difrangia
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3 hours ago, Rusty Dawg said:

Gotcha, I thought you we pulling my leg.  I'll get you a better shot.

 

I took my head to the machine shop and sure as heck there are several minor cracks.  He will clean it up and Magnaflux it to see if there are any major cracks.  He did say that the head was pretty warped and that this out of anything might have lead to water getting in my oil.  The cracks from what he can see seem to be minor and might not have been the root cause at this time, although he said it would eventually become a big problem.  Hopefully he can repair it since I am not certain I can find another head that is bolt on ready.

Sorry datzenmike, I am not sure what I was thinking, but my head is now at the machine shop.  I will try to remember to take a shot when I go tomorrow.

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Unfortunately, my head is a POS and although it very well could be repairable, I will start looking for another one unless the MGB head my machine guy had works.  I haven't tried to place it on the block, but it looks close.  There are a lot of cracks in mine and the valves are in pretty bad shape.  The only difference I see so far between the two heads, is how the valve/rocker arm cover mounts.  On the plus side, my rocker arms look like new.  Please let me know if you know of anyone with a good J13 head.

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Thanks.

 

Did not know they are closed chamber 'peanut' style combustion chambers. Lots of quench area on them.

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Someone has run that poor feller without water for way too long at some time in the past. If you do go with the Britt head, you can use one of these alloy covers unless you want to stay strictly original look.

 

E-1-Whiskey.jpg

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24 minutes ago, difrangia said:

Someone has run that poor feller without water for way too long at some time in the past. If you do go with the Britt head, you can use one of these alloy covers unless you want to stay strictly original look.

 

E-1-Whiskey.jpg

Not sure about going with the Britt head yet, but I could go for one of those drinks right now😁.  Is that a J engine with the Britt head?

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The engine in the pic is the original E1 in our 320 with it's original head and with the MGA alloy cover. I'm sure that the Britt head will fit on your J engine. I'm thinking that where you have to watch out on mixing British and Datsun J & E engine stuff is on the threads and gears. I believe that the crankshaft stroke (therefore the engine block deck height is different; pistons are the same in E-1200 and J-1300) is the major difference in the E & J series engines. I've never messed with a J engine. Distributor is a 1978 Datsun 620 'remote module' electronic, as opposed to 'Matchbox' electronic dizzy. We also have a 78 'Longbed' and I tried to incorporate as much from the 620 into the update of the 320 as I could to minimize spares in the parts stash.

 

The wiskey (probably a Bushmills or Jamesons) was a reward for another milestone on the engine build. I try to snag those rewards as often as I can, even if I have to fib a little.

Edited by difrangia
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Posted (edited)

I've been able to find 2 complete J13 motors in the NW for free as long as I arrange freight, so I might go that direction.  The individual just wanted to swap out to an "A" series engine on both vehicles.  Threads don't concern me, but when you mention that I need to watch out for things such as "gears" it makes me nervous.  Anytime I have to modify something to make it work, I tend to stay away.

Edited by Rusty Dawg
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J13 and E1 engines are both SAE threads, so if the engines that you are scouting out are J13's, Identified by the cast-in '1300' on the left side of the crankcase above the fuel pump as you've already identified yours, then you have no worries. Sounds like you may be onto a wealth of spare parts if transporting them is not a big $$ issue.

 

 The only gear issue that you'd need to keep in mind, that I'm aware of, is the distributor/oil-pump/camshaft gears and it sounds like you're not that deep into the engine. I can't recall the point at which the change-over was, but it was during the E1 production, that the gear tooth count was changed. Wayne, Ted, or another of the 320 Gurus on here can probably post details on the differences. Mixing British and Japanese parts is what I was referring to. I know very little about British machinery but believe that some of them use Whitworth fasteners.

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I found a head for sale that is complete minus the rocker arm and the dude is throwing in a J13 engine with transmission minus a distributor in case I need other parts.  He is based in LA and has worked on Datsun's for decades.  He also said he probably has gasket sets and other J13 goodies that he says he will throw in to help me along and thus get rid of items he has not used in over 25 years🤔.  I have transportation set up to pick up on Monday and deliver to me by mid-week. 

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3 hours ago, Rusty Dawg said:

I found a head for sale that is complete minus the rocker arm and the dude is throwing in a J13 engine with transmission minus a distributor in case I need other parts.  He is based in LA and has worked on Datsun's for decades.  He also said he probably has gasket sets and other J13 goodies that he says he will throw in to help me along and thus get rid of items he has not used in over 25 years🤔.  I have transportation set up to pick up on Monday and deliver to me by mid-week. 

Nice!

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On 3/25/2021 at 9:24 PM, Rusty Dawg said:

I've been able to find 2 complete J13 motors in the NW for free as long as I arrange freight, so I might go that direction.  The individual just wanted to swap out to an "A" series engine on both vehicles.  Threads don't concern me, but when you mention that I need to watch out for things such as "gears" it makes me nervous.  Anytime I have to modify something to make it work, I tend to stay away.

 

@Farmer Had a couple/few rebuilt j13s in Grants pass  .. Was awhile ago so might have tossed by now.. Would have to again arrange shipping but, having rebuilt might eliminate a few bucks in the long run.  

 

Google shows it's only 3 hours away from you,

 

 

 

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Edited by bananahamuck
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3 hours ago, bananahamuck said:

 

@Farmer Had a couple/few rebuilt j13s in Grants pass  .. Was awhile ago so might have tossed by now.. Would have to again arrange shipping but, having rebuilt might eliminate a few bucks in the long run.  

 

Google shows it's only 3 hours away from you,

 

 

 

.

 

 

I found 2 free engines in Bremerton, WA but freight was tough to secure and expensive.  Rebuilt engines might be worth my while.  How do I reach @Farmer shall my find turn out to be a dud?

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12 hours ago, Rusty Dawg said:

I found 2 free engines in Bremerton, WA but freight was tough to secure and expensive.  Rebuilt engines might be worth my while.  How do I reach @Farmer shall my find turn out to be a dud?


I think You should be able to click on the farmer name/ link and takes you to his profile. 
 

Also since I tagged him so might come here looking why he was tagged

 

I ain’t trying to steal someone else’s deal ,, just info and Farmer is a really good dude . 

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On 4/2/2021 at 11:06 AM, bananahamuck said:


I think You should be able to click on the farmer name/ link and takes you to his profile. 
 

Also since I tagged him so might come here looking why he was tagged

 

I ain’t trying to steal someone else’s deal ,, just info and Farmer is a really good dude . 

Unfortunately they have been long gone.  I think I found a head that is repairable, so I will proceed that way for now.  Thanks bananahamuck.

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I spoke with a guy in the Reno area the other day and he mentioned having a spare J series cylinder head. He's an MG guy and doesn't need it, and I tried to talk him out of it, but he said it's spoken for. Could this be the one you found? That would be ironic.

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10 hours ago, Stoffregen Motorsports said:

I spoke with a guy in the Reno area the other day and he mentioned having a spare J series cylinder head. He's an MG guy and doesn't need it, and I tried to talk him out of it, but he said it's spoken for. Could this be the one you found? That would be ironic.

No sir!!  The head and long block I found was south of LA.  The head was in much better shape than the one I pulled off my truck and my machine guy thought it was repairable since it was also cracked.  As for the head I took off the engine, I have yet to find out if it's the best of the 3 I have....I could see one crack without magna-fluxing it.  I appreciate the effort, but I think I might be good.  If not, I might see if the 2 FREE complete engines in Bremerton, WA are available and try to line up freight.

 

Thanks again.

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Well, we picked the best one of the 3 heads I have and repaired it.  It had 3 cracks in the combustion chamber.  The original head I took off my truck is probably repairable, but iffy and the other head I have is definitely repairable.  I will keep it for now to use on the engine block and transmission I picked up a few weeks back.  Never know when I might come across another project that could use it.  

 

Off I go to get this truck running again.

 

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Posted (edited)

So far, so good.  Only issue I see so far is a leaky valve cover....that SOB is leaking pretty bad, so gonna try a silicone gasket.  While I am in there again, I'm going to lash my valves once again since they are ticking a bit much.  Hopefully these vids post.

Datsun engine Cruising the Datsun

Edited by Rusty Dawg
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Silicone gasket cured mine after three cork gaskets failed. Mine has the cover secured by the two rocker tower studs. I was able to source a British application gasket. If you would, Rusty, post back where you find the silicone gasket for the cover with six screws securing it. The silicone gaskets seem pricey, but $$ is not the only measure of pricing.

 

Steve

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6 hours ago, difrangia said:

Silicone gasket cured mine after three cork gaskets failed. Mine has the cover secured by the two rocker tower studs. I was able to source a British application gasket. If you would, Rusty, post back where you find the silicone gasket for the cover with six screws securing it. The silicone gaskets seem pricey, but $$ is not the only measure of pricing.

 

Steve

Regardless of whether cork or silicone, I've yet to find a gasket with the bolt holes which is where 95% of my leak is taking place.  The silicone gasket I have I purchased from Moss Motors.  Not sure how it's going to work without the holes though.

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Check the valve cover itself. Years of constant tightening and over tightening may have dimpled the metal around the holes. No matter how tight you make the bolts, the cover isn't being clamped any harder. A hammer and dolly on the under side will smooth the dimpling out. Oil pans are another place that this happens.

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