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Valve cover gasket half moon fell into timing cover. retrieval?

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Im a novice not clear on alot about this truck but learning the hard way sometimes.  my question is-

Can i remove the oil pan and reach the half moon valve cover gasket i dropped into the bottom of the timing chain cover??

Could it possibly be in the oil pan?

 Does anyone know what it looks like at the bottom of the timing chain cover and how much room or opening  between the TC cover and the Oil Pan.



Yesterday i replaced the oil pump without spindle drive, distributor and TDC knowledge AND messed it up! Today i Had the valve cover off to watch and learn about valves, lobes, and TDC compression stroke works before i line up the distributor/oil pump drive to make it run like new again in perfect timing.

Then i notice the front half moon is missing..the back one was under the truck...Grief!

I see it at the bottom of the timing chain cover so i duct taped 3 foot of the skinnier water hose to my shop vac hose to suck it up. the skinnier hose made it down and grabbed it but it fell and not visible now. I tried more but No.. i need it to curve now to reach it. I can rig that up but Id rather just remove the Oil Pan for it but i dont know what it looks like down there and if that is just not going to work.


of course i need my only transportation here to get to work etc asap. 

Thank you for any/all help.


-Las Vegas NV.

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Wayne, you know what I would do? Just get another valve cover gasket and replace the one you have. The 'half moon' is soft and isn't going to hurt anything and if it gets to the oil pan it can't harm anything there either. I pulled a KA engine apart once and half the plastic timing chain guides were down there. A member here pulled his timing cover off and found the remains of a wooden wedge used to lock the chain to hold the tensioner in place when the head is removed. I guess someone forgot to take it out. Who knows how many miles that was in there.


I believe the half moons clip into place but it probably wouldn't hurt to rub a little RTV on them that will glue them in place. Sealer may even come with the gasket kit.

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It may not fall through into the oil pan. There is a ledge on the front of the block where dirty oily sludge tends to accumulate. It could get stuck there and never show up in the pan. I had a Rocker Arm Pivot-Guide pop loose. The engine ran strong on three cylinders to get home. I pulled the pan and no Pivot-Guide, It's the size of a dime and 4 times a thick. 25 years later, I pulled the engine to re-build it and found it glued into a little flat spot above and behind the chain tensioner. 

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Thanks very much for all the info.

A grabber tool would of worked the first time. Id of left it sitting there but since i still had the center link and cross bar out of the way already. ( left off the day before from replacing oil pan gasket} 

so i removed the oil pan again to get the "half moon".. it was too big to fall into the oil pan..but i was able to thump it a few inches for my shop vac water hose reducer to suck it up..  i was only able to get it thru the distributor hole only. (more room)

the other thing is i lost the distributor o ring too. (it was cold n windy i was rushing the work is why all the errors).

i thought id find it by vacumming more down n around the TC Cover.. no luck.. then reversing the shop vac hose and blowing air from the top then bottom of Timing chain cover to see it fly around but no. i blew air everywhere to see if it got stuck below fan or frame... wheel wells...everywhere..  but its so missing it doesnt exist. good riddance!     i walked to Autozone for the assortment o ring pack i read about here to get it done.. today.  

The oil pan is back on.  oil is back in and valve cover back on with dabs of permatex rtv on gaskets to make them all stay put. 

Tomorrow i hope i get the distributor/oil pump timing lined up.


1  TDC compression stroke.

2  Dist on and rotor pointing to #1 exhaust plug terminal. 

3  install oil pump to fit dist.

4  crank it up

5  timing light.check..  still on 3 degrees i hope. i have it marked.

 Post results tomorrow.

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The two front cam lobes should be pointing down at 8 and 4 o'clock as viewed from the front and is just a visual to let you know you are on the compression stroke and not nearly accurate enough for setting the distributor.


Use the notch on the crank pulley and line it up with the timing scale near the alternator for TDC.

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Ok . ive had to remove the v cover bolts again so i can lift the v cover to MAKE SURE the lobees are down then adjust. im not sure otherwise. i finally got it to run at 50 %. i think my rotor button is going to pointing at near 9 o clock to run perfect. its at 845 now and today ill drop the o pump and twist it a bit more and it should begin idling  smoother. the 2 crescents will probably read 12 35 instead of 1128.whatever makes it run perfect again. this is the 5th day correcting  this mistake. almost there.

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The ignition timing is totally separate from valve timing. Set the V groove in the crank pulley to zero on the timing scale







The piston is now at TDC. Pull distributor out and look in the hole. You should see this...




Drop oil pump and adjust drive spindle to get this orientation. Note the large and small half moon position. Distributor will now go in with the rotor pointing to #1 intake and exhaust plugs on the cap wires. In my experience the rotor is 9 and 4 o'clock roughly. It turns counter clockwise two positions to get to the #3 intake and exhaust then 2 more to #4 intake and exhaust and the last 2 for #2 intake and exhaust. The next 2 will bring you round to the start.


There are 8 plug wires and easy to get them cross wired.



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Having to re type this post it didnt stick so ill be brief in case ive used up all my posts.. newby.


Thanks for pics..i finally suspected plug wires sure enough 1i at 2i      2i at 1i    and 1e at 1i  locations.   total mindblowing surprise!

Maybe no big deal but i cant get the rotor buttons to line up at 9 n 4.  everything right on and mine is at 7 and 2.

it has ran up to 50%.    Another 8 hours tomorrow maybe it will come to me.


i wonder if the prior   T chain replacement was off and the mechanic compensated  o pump/ distr location and nailed it..runs 100%??

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The timing chain controls the valve timing (valves opening and closing).  The distributor, and the ignition (spark) timing.

Def don't worry about the piece of gasket.  And just to make you feel better - the first time I did a head gasket, I dropped a washer from a head bolt down the timing chain cover.  Learned a lot with that - but started me on a lifetime of fixing my own cars.  


Also - no limit on posts.  

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Thank you 1i at the 9 oclock 1 e at 4 was another question i had...ive never read that detail anywhere yet. thats important.

Right on...its time to stay attentive how these parts work together .... At the end of yesterday i noticed  1e 2e 3e 4e 1i 2i 3i 4i  marked on the dist cap to make it easy. will study cap n wires locations thoroughly  set it up right...check thrice...hopefully finish with the timing light. i need to get back to work its getting serious.

i totally appreciate getting all this info.  i wonder if its possible to have the dist cap on upside down.  

so glad theres a problem to correct today.  

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Its running good now. the wires were correct on the distributor but i had to switch the wires at #1 and #2 intake plugs. this is how i swithched  the !&$%***^%#ckers.     i was going to remove all the intake plugs for ease of TDC and only got as far as removing the 1 and 2 wires.   i changed my mind and put them back....i would only remove #1 ex plug for TDC which ive had to remove 47900 times this week because it never ran right with those wires crossed.  The timing light says the mark is lower than the scale and i know i have to repeat the process 1 more time to get the drive moved 1 more slot and mark will be back inside the scale. i never loosened the bolt that allows the dist to move left n right for timing so i think the mark should land back at 3 degrees. i hope this lesson was supposed to happen otherwise i dont appreciate it. at all. woulda only took 1/2 day if wires didnt get switched. 

i appreciate you guys though and ill report the final results tomorrow. day 6. more like 3..i goof off alot.

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I woke up early feeling good. at 7 am i moved the drive spindle a bit more to the right (another slight 1128 position)  hookup timing light and the timing mark landed on TDC or 0 on the timing scale. i think i could move the drive a bit more left and it would be at 3* but why? 

Herea a serious question..  ISNT THAT WHAT  turning the distributor left or right is for..? being able to move the mark within the scale. i only had to move the cap

left about 1/8 of an inch counter clockwise.   It runs and drives so good... im  addicted i love the thing.

i decided to retorque the head bolts as ive read so many times how. loosen then re torque one at a time. the thrill was when the wrench clicked after

reaching 60ft lbs all  were  done and nothing broke.   im doing the valves next.


HERES another good thing today. The valve adjustment on hot engine set to 12. ive read people do it several ways..cold engine hot engine 8- 14 degrees

I BELIEVE HERES THE BEST WAY. it mattered on mine today.

The first try after prepping. basically just leaving 4 bolts on valve cover to remove it quickly.... then idle to hot engine...adjust all valves.. but

after firing it up i noticed the temp guage needle was down 3/16'' cooler even after only  5 mins during the adjustment process .....so


i fired it up to hot engine again... then with lobes up at TDC i adjusted only the last 4 valves that had cooled and sure enough they needed a bit of correction especially the last one for me was intake #4. its dead silence now except the chain slap is more clear to hear. even racing the motor quite high  they are quiet.solid. peace of mind.


Im going back to work. not going to be kicked out on my ear homeless AND without transportation..O  H   N!

this is my only ride.. if your ever in LV and see a copper King Cab hauling 12' carpet rolls and pad all over the place... flash ur lights n wave.. therego knothead.

I plan on retiring her next fall for pleasure only. im getting a transit connect for working.  NEXT REPAIRS....Timing chain and rear seal.   Ratsun Rules.                 ---                                                                                                                            ===END===

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Yes, you only have to be within adjustment range.


Re-torque should only be done on a cold engine when the head and block are not heat expanded.


If you set TDC you can quickly adjust, (from the front) valve 1, 2, 4, and 6. Then turn engine ONE turn back to TDC abd adjust 3, 5, 7 and 8 and you're done befor it cools off. This eliminated constantly bumping the engine over to close each valve.


What oil are you using? All oils today have reduced anti scuff ZDDP levels that out vintage 'flat tappet' engines need. Use oils marked 'racing oil' or diesel oil that still have the '70s level of ZDDP in them. I'm fond of 15W40 Shell Rotella T (I think renamed T4 now) or Chevron Delo 400. The thicker oil will slightly boost oil pressures at low speeds and quiet the engine. I've had other 720 owners say that their 720s make noise to tell them it's time to change the oil. Always change the filter with the oil and get a good WIX or NAPA Gold filter not fram.

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That makes sense.  the locknut is still in the middle of the dist adjust range.   my last post was out of order.  i was confident i had the oil pump done then i re torque the head bolts while cold. Then warmed it up and checked with timing light.  Then on to valve adjustment.  Just before all this ive been  interested and reading about  torquing bolts and motor oil . i bought a torque wrench   (i still need a small IN LB wrench)  and have even the spark plugs torqued right...on cold motor also.  and a few weeks ago i changed over to delo 400 after reading about zinc. i had chose regular valvoline race oil... not the xp  but couldnt find it stocked at napa and carquest. i think the xp is good for 3000 miles (ok for cat converters} and the      ''higher zinc regular'' is recomended to be changed every 500 miles (not for cat converters}  so ill just stay with delo or rotela.


I didnt notice any chain slap today.  I use a hidden remote starter button inside the cab and crank it over on cold mornings before starting it.   oh i did remove a little bit of chain guide plastic when i dropped the oil pan for a new gasket     that was all that was in there..glad to know what that was. Thats something about that wood wedge you mentioned that was left behind id like to meet that guy n give it back. LOL


The whole reason why this work has come is from the oil leaks that has started the last 2 months and was getting quite noticeable. Oil pump replacement was just because its a good little truck.    the 1st couple years i owned it i did use  fram sometimes, i didnt know better.  and ive always used Mobile 1030 synthetic   Last summer in Vegas it was so dangerously hot as Hell  maybe the heat helped pushed oil past the gaskets.   ive only been in Vegas for 5 months and last month i had to drive all the way to xxxxx New Mexico and back just to renew my license...a 1300 mile round trip.  (im not ready to put my cat back on..pass smog ..get NV license/insurance yet}... im holding out til next fall.

i decided to just change the  filter and go and i put a darn fram on. id change the oil and filter after the trip. i have a feeling fram has sped up oil leaks. i have a Napa  Mobile1 m1-301 on now.    Anyways burning 1300 miles with no concern  may prove the confidence i have in the trucks reliability.. NM residents must show up in a physical license office to renew,, i love road trip no big deal.  its hard to cash checks with expired driver license.

A few months ago i also replaced a seriously leaking high pressure hose.  Now only the rear seal is leaking.  Ill be 0.5%  no  100% prepared for that Beforehand. 

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The high zinc content only applies to the newest catalytic converters. The 720 is over 30 years ago and the converters back then were different and so was the oil. It's only high zinc content compared to the oil made today. It's actually the proper level for 30 years ago and today's oil is better called low zinc. Best to run the oil that our engines were made to run on.


Oil leaks are oil leaks and from old gaskets not the oil filter you use. I don't like synthetic for this very reason.... it leaks past old gaskets and seals because it's so thin and slippery. Old Datsuns don't need the extra lubricating qualities of synthetic oils like newer engines.


Fram are just cheaply made and there are much better ones for the money is all.

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