Didn't block timing chain...

[datzenmike]

Besides it will still pop out if you don't block it.

[68Datsun510]

Nope. While i wouldnt try it without a block, common sense. The tensioner will not fall completely out with the chain in place.

[Stoffregen Motorsports]

I always manage to strir up a good controversy.

 

I hate to pull rank, but I've built at least 100 L-series motors, and all of them have had the spring cut. And the company I worked for built many more and still are.

 

If you look, there's an oiling orofice in the back of the tensioner body which provides oil pressure, usually 50 psi or so, to keep the chain tensioned. That's a lot more than the spring does.

[datzenmike]

I.... don't agree totally with this. If that's the case why did Nissan make the spring so stiff? and it is really stiff. They could have done the same thing or left it out. The plunger is barely 0.575" across or 0.259 sq. in. so my L20B idle oil pressure is 29 PSI and the plunger is then pushing only 7.52 pounds. At 50 PSI that's only just under 13 pounds. I would leave the spring full strength.

 

Not saying you can't, just that the oil doesn't do that much pushing.

 

[I'm BLUE]

I've had 1 head-bolt break off below the sealing surface in the block.

Spent a few hours after work trying to work it out/drill ... mostly scratching my head and tinkering a bit at a time with no haste.

I finally got the broken bolt out .... heli-coiled it ... and it worked just fine.

slapped the head back on and was good to go !

 

This particular area of the block "seeped" just a bit of coolant at a time ...

I'm guessing straight into the thread ... and worst the engine sat for years !

 

That was the worst bastard of a bolt to drill out for whatever reason.

I've drilled quite a few to know now lol.

 

head-bolts in these snap right and left. ( at least on me with used engines and even my own ... )

It's amazing to see how much the bolt's themselves "flex".

 

If a must ... new bolts/washers can be had from the dealership.

I spent about $72 for a whole set from Nissan with washers.

 

 

avoid drilling if you can. When welding a nut ... a little at a time ... cool down ... then hit it again ...cool down.

[Stoffregen Motorsports]

Not saying you can't, just that the oil doesn't do that much pushing.

 

 

It's under oil pressure. How much pressure does your L motor have? More than spring pressure?

[68Datsun510]

Mine sits at 18-20 at idle, and 50-60 at speed depending on temperature. Seems like enough.

[Z-train]

I always manage to strir up a good controversy.

 

I hate to pull rank, but I've built at least 100 L-series motors, and all of them have had the spring cut. And the company I worked for built many more and still are.

 

Just because something "doesn't go wrong,doesn't mean it's a good idea.THe factory guys weren't idiots.They did it for a reason.And unless you been wrenching on Datsuns before 1976-you're a JUNIOR officer.

[68Datsun510]

Lol, love the "there is only ONE way to do things EVER and it was written 45 years ago and NOTHING can be improvised or improved upon" ideology.

 

Agree to disagree i suppose.

[Z-train]

One way?Nope.THere is always more than one wayThe right way however,is the factory way.THere is absolutely NO benefit to cutting the spring.

[datzenmike]

It's under oil pressure. How much pressure does your L motor have? More than spring pressure?

Well...

 

I.... don't agree totally with this. If that's the case why did Nissan make the spring so stiff? and it is really stiff. They could have done the same thing or left it out. The plunger is barely 0.575" across or 0.259 sq. in. so my L20B idle oil pressure is 29 PSI and the plunger is then pushing only 7.52 pounds. At 50 PSI that's only just under 13 pounds. I would leave the spring full strength.

 

 

I measured the diameter of the plunger (0.575") X pi R squared to get the area of the plunger, about 0.259 sq in. Hot idle oil pressure on my L20B is 29 pounds per square inch X 0.259" = 7.52 pounds of pressure. 50 PSI = under 13 pounds of pressure. I don't know what the spring pressure is against the chain but it's a bitch to get the plunger in and hold it while installing the chain.

[80daterpillar]

I've had 1 head-bolt break off below the sealing surface in the block.

Spent a few hours after work trying to work it out/drill ... mostly scratching my head and tinkering a bit at a time with no haste.

I finally got the broken bolt out .... heli-coiled it ... and it worked just fine.

slapped the head back on and was good to go !

 

This particular area of the block "seeped" just a bit of coolant at a time ...

I'm guessing straight into the thread ... and worst the engine sat for years !

 

That was the worst bastard of a bolt to drill out for whatever reason.

I've drilled quite a few to know now lol.

 

head-bolts in these snap right and left. ( at least on me with used engines and even my own ... )

It's amazing to see how much the bolt's themselves "flex".

 

If a must ... new bolts/washers can be had from the dealership.

I spent about $72 for a whole set from Nissan with washers.

 

 

avoid drilling if you can. When welding a nut ... a little at a time ... cool down ... then hit it again ...cool down.

 

Thanks for the answer/advice, will take it slow for sure. Thinking I might try getting new head bolts, I know guys say to reuse, but I don't know if it's worth the risk...

[datzenmike]

They are totally reusable. As long as they are not damaged and the threads and the hole threads in the block are clean. if in doubt replace them but you still have to clean the block threads, wipe the bolts threads with an oily rag and put a drop of oil on the washer under the head bolt cap.

[Stoffregen Motorsports]

Just because something "doesn't go wrong,doesn't mean it's a good idea.THe factory guys weren't idiots.They did it for a reason.And unless you been wrenching on Datsuns before 1976-you're a JUNIOR officer.

 

You're kidding right? You must be, because if you're serious, you must be delusional.

[Stoffregen Motorsports]

I love these arguments. I fall back on success. How many times have I been successful in doing this "spring cutting taboo"? Lots, how many failures of said tensioner or associated components? None. Let me say it again NONE!

 

If you guys want to beat you head against the wall building the same old stock crap all your life, go with God.

[80daterpillar]

This is just a cock contest at this point, does anyone else really give a shit???

 

If you don't like it, don't do it. If you want to take the risk, go ahead... Can we all move along now..?

[Dat Lurka]

No!

Fuck you!

What are we dicking about?

 

If it's not broken

don't fix it

Unless it makes it go faster

[Sealik]

Soooo...what was the point in cutting the spring???

 

Maybe 'conducive' for a freshly rebuilt engine....but....what happens when the motor has a hundred thousand plus clicks on it?

Chain stretch........ and excessive rod/main bearing clearances which results in lower OP

A stock full length spring would be a given at that point.............

[nismo dr]

go with God.

http://www.youtube.com/watch?v=eujCeBC4Lh0

[Dat Lurka]

hmm back a page....

cutting tensioner spring??

Lolwtf

No...

That's silly.

[Stoffregen Motorsports]

This is just a cock contest at this point, does anyone else really give a shit???

 

If you don't like it, don't do it. If you want to take the risk, go ahead... Can we all move along now..?

 

You're right. I was trying to explain an old trick, a trick used to keep the tensioner from popping out when you removed the cam gear. There is no performance advantage to doing so, but the OP wouldn't be here now if the factory had installed a shorter spring.

 

I just love the factory engineers argument. Ford used engineers to design the Taurus automatic trans, why did that turn out to be such a piece of shit?

 

Can't we all just get along?

[68Datsun510]

And the powerstroke, and the bronco II, and the Aerostar, and the Ranger..... :P

 

Its a racecar trick so shit doesnt go wrong trackside when seconds count in the pits or between races, been used by several reputable companies and entrepreneurs forever, no ill effects. bottom line? its been done for a long time, ever see an L toss a timing chain? on the track?

 

This reminds me of the argument that I WILL toss lash pads because I dont have aluminum tall retainers. Guess what? Nope! Keep your valves adjusted, no problems.

 

OP, pissing contests aside, have you gotten enough info to fix your problem?

[Dat Lurka]

He fudged up

I fudged up too

Next time

Block that chain yo

 

[Dat Lurka]

And the powerstroke, and the bronco II, and the Aerostar, and the Ranger..... :P

 

Its a racecar trick so shit doesnt go wrong trackside when seconds count in the pits or between races, been used by several reputable companies and entrepreneurs forever, no ill effects. bottom line? its been done for a long time, ever see an L toss a timing chain? on the track?

 

This reminds me of the argument that I WILL toss lash pads because I dont have aluminum tall retainers. Guess what? Nope! Keep your valves adjusted, no problems.

 

OP, pissing contests aside, have you gotten enough info to fix your problem?

 

Hey

I got an aerostar

It's got lots of room and gets 25mpg hauling rednecks to the lake.

Slow as fuck on the highway though

[80daterpillar]

All things aside, great thread. Sorry to see the originator drop his tensioner, however it did save me from losing mine... That's what Ratsun's for right? :thumbup: