38/38 Weber outlaw vacuum setup.

[banzai510(hainz)]

OK you going to have tho rotate the cam lobe so it pointing out of the way like more UP.

 

now your going to put the valve pad back in and then youl need to break the 17mm  nut and rotate the rocker arm pivot ball down much as possible.

 then using some screw driver(s) try to leverage the rocker arm back on.  Some times I put the rocker in the slot of the lash pad and go to the back side where the pivot ball is and lift the rocker up from there onto the ball .  really ist EZ.

then re adjust the the lash by rasing the ball back up with the 14mm then locking the 17mm nut . then run the motor and see if it happens again.

 

Every now and then they fall out. I adjust mine .006in and .008 COLD.  other do it more loose and hot

[TheBirdistheWord]

Okay, I will reassemble and report back. Thanks for the guidance!  

Is there any chance I will need to remove the head? For instance could the valve seat be FUBAR or more abstractly could it have separated from the valve and be loose in the cylinder?

[datzenmike]

Too early for thinking that. Put together and see if that fixes the problem first. The valve head is much larger than the valve seat so it can't slip off that way, unless broken. They are pretty tough so unlikely.

[TheBirdistheWord]

Well, doesn't seem anything is messed up too bad.  Got everything back together, adjusted valve clearance I bit tighter, and made damn sure the lock nuts were tight.  No funky noises after firing it up and revving it a bit. 

 

I'm so relieved I didn't cause any crazy damage.  This is the worst of it which after filing down the sharp edges I'm not too worried about thanks again for the help everyone.  Still undecided on a throttle linkage solution but seems fine for now. 

[datzenmike]

I would begin searching for another head that has a cam and all the rockers. No rush, just start now. Try for a U67 head. Maybe rebuild it with the hardened valve seats.

[banzai510(hainz)]

hopefully the scarring on that cam lobe is on the back side. so it don't wear the rocker arm to much otherwise you should be fine.as your valve lash gap will miss this

[TheBirdistheWord]

On 2/15/2020 at 7:46 AM, datzenmike said:

I would begin searching for another head that has a cam and all the rockers. No rush, just start now. Try for a U67 head. Maybe rebuild it with the hardened valve seats.

Unrelated to this i had just recently picked up a 210 head that was supposedly built by rebello. Taking that with a grain of salt as there's no way to really verify but the price was right and if it has enlarged valves I'll consider it a win regardless of who built it.  Doesn't have cam and needs to be tanked and inspected before use either way.   The engine that this one replaced has a smog head that I could swap cams with.  The aforementioned "rebello" head was meant to go on the napZ block I picked up a while ago so I'm leaning more towards swapping cam with old engine.  I wanted to sell the smog engine to help fund the start of the LZ build so might be upgrading to a mild street cam instead. Decisions decisions. 

 

21 hours ago, banzai510(hainz) said:

hopefully the scarring on that cam lobe is on the back side. so it don't wear the rocker arm to much otherwise you should be fine.as your valve lash gap will miss this

Im pretty sure it's unfortunately on the lash side of the lobe so I think I'll be looking to swap out the cam. 

[banzai510(hainz)]

If scaring is on lash side I think your fine as it will never touch the rocker arm/cam lobe

[TheBirdistheWord]

35 minutes ago, banzai510(hainz) said:

If scaring is on lash side I think your fine as it will never touch the rocker arm/cam lobe

Ohhh right, that's where it has the most clearance! I was thinking about it backwards. 

[TheBirdistheWord]

So, figured I'd revive this thread since it has most of the pertinent photos.  

 

I'm getting funny surging at warm start and severe bogging off throttle. This morning started getting back firing through the carb. Verified timing is correct. From what I can tell through using my googlefoo is the afformentioned intake valve that had the rocker arm fall off is f#*$ed.  Adjusted the valves less than 20 miles ago with the engine warm and this intake valve seems to be in the correct adjustment. Was a bit chattery before the backfiring so I'm hesitant to back it off a bit to see if it's too tight and not closing all of the way. Whatever. Chatter be damned, gonna try to see if loosening valve helps the backfire

 

Other than pulling the head are there ways to confirm before I pull the head?  I have a 210 head that I picked up for $30 getting cleaned up for use just in case there is damage on this peanut head. 

 

Guy I brought my head to has this cam for sale. Can anyone help me ID the duration? I've had no luck with isky site.

Edited April 14, 2020 by TheBirdistheWord

[banzai510(hainz)]

480 lift and I bet 280 duration 

zcardepot.com shows this cam 

 

go on web and put in isky  c amshaft Datsun and it gets in there and list cams but might be old listings

 

Bogging is common on the 38s especially on a hillside 

 

warm start to me be a choke issue.if anything it might run better with the choke on at lower rpms till the choke plate kills off the air supply at higher rpms

 

give him 100$ for the cam

Edited April 14, 2020 by banzai510(hainz)

[datzenmike]

Primary jet part blocked causing a lean backfire. Possibly accelerator pump on one side blocked or poor discharge volume.  Won't show up as lean when cold because choke forces an over rich condition during warm up. Will cause bog off idle when not enough gas supplied for the added air when the throttle opens. Also carb too big.

 

[banzai510(hainz)]

Ez to check the accel pump by looking as you cycle the carb

 

as for the primary jet you still have the second barrel jet so I assume you would not notice until there is more demand for fuel

[TheBirdistheWord]

So, lossened the valve just a smidge. No more backfiring. The spark plug in the 2 cylinder was drenched in fuel. All other plugs were fine. Ive had some luck with running issues with going back to both idle circuits being open. One is at 1 turns out the other at .5 still surges and boggs at idle slightly. Going to run it around the block in a few minutes to see if it's reliable.  

I'm not using a choke at the moment. Accelerator pump(s) seems fine. 

 

My 1st Gen Tacoma's water pump is leaking with less than 10k on replacement. So I kind of need this thing to be solid to get me to work. 

Edited April 14, 2020 by TheBirdistheWord

[TheBirdistheWord]

Could this cam potentially be a better match for the carb?

[datzenmike]

Yeah above 4-5K. More lift and duration will allow more air to flow. The down side is loss of manifold vacuum that makes for a smooth idle and low speed running.

[TheBirdistheWord]

Hm. Well seems I'm already sacrificing that so I may pull the trigger and have him install it when he's done cleaning the 210 up. 

[datzenmike]

Uh yeah a 210 head.

 

This is the smallest valve and port head the L series has. Even rumored to be designed for the L14. It's really going to limit potential of the 38/38 and a cam.

[banzai510(hainz)]

38 on a 210 L16 Head  is already a bit much unless you port the shit out of the head Which most are 1.25 on if that on a 210 head. Most are 1.25 and L20s are 1.375

sssheads are 1.50

 

i would start with a better head as the ports are larger and the valves and waist in time and money putting that cam in a 210 head

Edited April 14, 2020 by banzai510(hainz)

[banzai510(hainz)]

3 minutes ago, banzai510(hainz) said:

38 on a 210 L16 Head  is already a bit much unless you port the shit out of the head Which most are 1.25 on if that on a 210 head. Most are 1.25 and L20s are 1.375

sssheads are 1.50

 

i would start with a better head as the ports are larger and the head and waist in time and money putting that cam in a 210 head

having a small weiner and buying Xtra large condoms isn’t going to work right

Edited April 14, 2020 by banzai510(hainz)

[TheBirdistheWord]

Lol, believe it or not I actually new that about the 210 already. I'm just flustered and scrambling to have a vehicle to use... Ill likely put cam in the a87 head that's installed currently, as it's already got the valve stems/seals and light port work. Working with what I currently have on the parts shelf, I'm aware that there are better options. Ill Have the 210 head as backup in stock form.  I've got a w58 smog head that I may choose to put some money into. But opinions on if it's worth the effort is a mixed bag. 

[datzenmike]

It's a fine head though I would prefer a U67. If you go with a W58 have the exhaust liners removed when the valves are out. The same liners are in one of the Z car heads and it goes just as fast as ones without them. The W58 is called a smog head because of the liners and given the choice people will shy away from the word smog. I don't think there is any hard dyno evidence that they run less well than a U67 head.