L16 Timing Chain Noise

[Augusta2]

Need some help. Bought an SCCA ITC 510 and plan to road race in NASA. Rebuilt the 32/36 weber and have done all the compression checks etc. As I increase rpms I have a metal noise at the very front/top of the valve cover. Noise goes away at high rpms. Pulled cover and there are some scratch marks on the inside directly over the timing chain.

 

Valves are good etc. Chain appears to be loose, but I can find no way to check the specs on how tight the chain should be and need to know if there is a way to adjust tensioner etc without taking off all of the front parts and replacing guides, tensioner etc.

 

If that is the recomendation from the group. What should I look for in a kit and where?

 

Nick

[Skib]

Chain appears to be loose, but I can find no way to check the specs on how tight the chain should be and need to know if there is a way to adjust tensioner etc without taking off all of the front parts and replacing guides, tensioner etc.

 

 

either way, your going to have to pull the front cover to get to anything timing chain related.

[banzai510(hainz)]

olddatsuns.com has my L series timming chain install vedio.in tech section.

 

Have you tried another valve cover??????????

 

OK time put motor to TDC keep the chain tight then look at the timming marks is cam is timmed. If it is then look at the slack side and see if real loose. What is real loose.?

 

PS dont NOT get the Cloyes or Mellig timming chain kits.

Find a Jap set one with the 4 holes(in cam sprocket) Tsubaki,OS Giken maybe Beck Arnely

 

try importedcarparts.com maybe others

[datsunaholic]

You're going to have to take off the timing cover. I've heard of folks putting stronger springs in the tensioner, and there's a REALLY expensive adjustable idler tensioner setup out there (like around $650).

 

Of course, if the head has been milled or the block decked, you'll have trouble getting tension since the distance between sprockets has shrunk. If headsaver shims were used, then the cam sprocket-valve cover clearance would be reduced.

[Augusta2]

I have watched you video and it is great. I guess the question is how loose is loose and what the ramifications would be if i just left things alone for road racing. The slap goes away (under load I guess you could say) Engine is timed ok. Would just replacing the tensioner and guides take care of things. I have not tried another valve cover.

 

 

 

olddatsuns.com has my L series timming chain install vedio.in tech section.

 

Have you tried another valve cover??????????

 

OK time put motor to TDC keep the chain tight then look at the timming marks is cam is timmed. If it is then look at the slack side and see if real loose. What is real loose.?

 

PS dont NOT get the Cloyes or Mellig timming chain kits.

Find a Jap set one with the 4 holes(in cam sprocket) Tsubaki,OS Giken maybe Beck Arnely

 

try importedcarparts.com maybe others

[datzenmike]

Measure the thickness of the head from the valve cover to the block. It should be 4.248" or just a hair under 4 1/4". Anything under that and it's been planed down. One mm doesn't sound like much but it's almost 0.040". A head milled this much will add 0.080" of 'extra' chain slack

 

Use a flash light and look down between the two guides and inspect them for wear. Can you see the tensioner? Is it in place?

[banzai510(hainz)]

Persoanlly If I race I want to know what I have .

 

the Valve cover? I had one that if I did not use a gasket it would hit the cam tower. tried another it would not. so maybe when you have a gasket on there is close enough to hit at a certain engine speed.

 

 

Be honest I havent seen to much cahin strech myself But its alway good to put another new tensioner and slack side guide on there if you take the front timming cover off. I always use the Felpro front cover gasket set.(shucks,kragon/checker have them or can order them.

[RoadRace]

 

PS dont NOT get the Cloyes or Mellig timming chain kits.

Find a Jap set one with the 4 holes(in cam sprocket) Tsubaki,OS Giken maybe Beck Arnely

 

try importedcarparts.com maybe others

Hainz- whats wrong with Cloyes? i have used them in very high output max-effort V8 applications with considerable success. just wondering.

[banzai510(hainz)]

The Cloyes or Melling have a Made in USA Cam sprocket. At least the 2 kits that I bought.

the inspection holes are in the wrong spot, so if you want to look thru the sprocket to see the V notch and dash. YOU CANT!!!!!!!cause they put the oval hole in a differnt spot when they cast them. Notice they will have 3 holes.Jap ones will have 4 holes or the multi hole version

So if you wont to ck chain stretch YOU CANT.Also if you do a head gasket and forget to mark the chain you could be off a tooth and might never quite know it cause you cant see the timming marks. car/truck will still run fine if off a tooth. To make best power you want the timming correct

 

 

Maybe they are OK build wise and for other cars but that what I notice Plus in their kits if the chain dont say Japan its most likely a taiwan chain(like the ones in my kit). They wont have the BRITE LINKS on them either.

 

I have the Jap timming chain kits now.

 

Nowadays most aftermarket parts they pc the cheapest parts together. Some maybe were all japanese at one time but now even the bigger names have outsourced parts.

Napa use to sell Quality made parts. Now most is mexico and now China!!!!!!!bearings, Drum brakes ect........

[Zendar]

Is this timing kit any good?

click here

click here for bigger picture

[banzai510(hainz)]

the kit looks OK. But I dont see the brite links on the Chain. I will assume its taiwan made chain.

[Zendar]

In the bigger picture the chain seems to have at least 1 darker link in the second row?

 

I've been searching for a tsubaki kit some time now and can't seem to find a seller that doesn't ask silly amounts of money for shipping. The kit has been like $80 but they ask over $100 for shipping to Finland and thats just outrageous.

 

Can you help me out hainz? :P

[banzai510(hainz)]

http://catalog.eautopartscatalog.com/archsoftware/importedcarpartspfp/wizard.jsp?partner=pacific&year=1971&make=NI&model=510--001&category=A&part=Timing+Gear+Kit&partnerSession=c760427c97f03cf7ea725f401c1ccb6f

the kit above I have and does have the brite links. However its not in the picture.

importedcarparts.com

Maybe the ebay one is good. I cannot verifly that brand(box) Im sure if its a taiwan chain it would still be OK

 

a timming chain kit for a 240z,260z,280z 6 cylinder will fit also. as the blocks are the same height and same timming cover. Only the L20 b is taller and have a longer chain.

 

ask thss guy he lives in Norway where he gets his Datsun parts

Yngve Tidemansen [tidemansen@hotmail.com]

or

http://www.datman.co.uk/ (from England)

 

unfortunatly one has to pay shipping and a Import Tax.be honest most times the chains are OK its the slack side chain guide and the tensioner that wear the most.

[Zendar]

Thanks for the link, I emailed them about shipping, also emailed to the ebay auction lister about the kit (where it's made and such).

 

You hit the jackpot on the reason why I'm in need of a new kit. My slack side guide and tensioner are badly worn and I won't be using them.

[banzai510(hainz)]

Zendar

I can look I might have a Taiwan made Tensioner and a Japanese slack side chain guide.

 

private message me or wait till tommorrow

 

I might have given it away already I have to ck

[Zendar]

My local part store seems to have guides and the tensioner for LD20. I'm gonna go check tomorrow if they will work.

[datsun mechanic]

oil pressure to tensioner as i recall comes thru hole in crank main bearing .......is tensioner getting enough pressure

[banzai510(hainz)]

Zendar

LD20 is a Deisel?????????I know nothing about diesels

[Zendar]

Store had also L24/26 guides and tensioner, they had the same part number as the LD20/28 parts, I ordered the L24 parts. Will see in a couple of days if the parts supplier can get them anymore.

[banzai510(hainz)]

Let me know aas I have a tensioner(used only 5 miles on it) and a used but good slack side guide)

I have it boxed up.

If shipping dont costtoo much Ill sent it to you FREE.

 

PM me with your adress and email

[banzai510(hainz)]

Package with tensioner ,slackside guide and various gaskets in box on way to Finland. Hope it dont take too long

 

No I dont have 620 enine mounts. I have some for 510/ 521

 

 

Datsunaholic is more a truck expert PM him. He might know what can be changed from a J series motor 620 to a L series 620

[Augusta2]

Thanks Hainz,

 

Here is what I found,

 

Chain Tensioner came loose and wedged itself against the slack shoe.

 

Cam is an Isky L-7

 

Cam is in the number 3 position, bright link appears to be a little off.

 

Cam cover has a crack in it.

 

Distributer was not at 11:25, more like 1:7

 

Could you guys review and make suggestions on timing and cam cover crack

 

Nick

 

 

 

 

[hang_510]

Cam cover has a crack in it.

 

Distributer was not at 11:25, more like 1:7

JB weld or replace the cover. i have a few.

 

 

pull oil pump, reset to the 11:25 poisition when #1 is @ TDC.

 

 

#3? maybe time for a new chain.

[banzai510(hainz)]

going by the cam sprocket "V"indentation it looks RIGHT ON!!!!!!! Now thats with the lower crank pulley at zero and all the slack out of the chain on the right side

Its the yellow paint that make it look like its off. Now I dont know if the yellow paint is the true markings(maybe they degred the Cam).

As for the paint on the chain sometimes it take awhile to come back out in the correct spot after the motor has been turned over. Most time its for intial set up.

 

When you say Cam cover? You mean like the whole Valve cover or you mean timming chain front cover as I cant pitured where that crack is. Looks like inside of a timming chain cover to me.

 

Front covers and valve covers are EZ to get here. I dont know in Viginia used.

 

 

also note I see the lower sprocket but I see slack on the right side. Anytime when doing TDC to ck for timming the right side should have all the slack taken out when you dial crank up to Zero. then pull the front timming cover off

[Augusta2]

The timing chain front cover has a hairline crack in it.

 

My plan at this time would be to just

 

Reinstall the tensioner and new guides

 

Reinstall the distributer correctly

 

Keep timing as is for now and see what happens, what do you think?