Jump to content

Off by a tooth


PATHRIDER
 Share

Recommended Posts

Ok guys Im working on a 92 Nissan Hardbody (D21) timing belt. Followed the instruction on all the install procedure on here and did my Pathy and the wifes many years ago with no problem if I remember correctly and correct me if Im wrong here, Arent the D21 has the same motor as our pathy? VG30

 

To make the story short , When I was putting on the new belt both L3 and R3 cams lines up with the marks and tooth count is 40. Now going from L3 to the crank pulley Im a tooth off (counting at 43 to the crank pulley mark)

 

When I started this project I set it to TDC , rotor is pointing at spark plug wires 1 removed all the covers and everything was lined up on the old belt , however theres no visible marks like white dots like we do on our pathy, I just went by the dimple on the cams back plate and now marked with a white dot and the indent on the cam sprockets also now marked with a white dot ..The crank pulley also has no visible marks when I first took the bottom cover but after cleaning it with sprayway glass cleaner which by the way just melts those nasty grime better than using more harsh chemicals like brake cleaner or gasoline I can see the tiny indent on the crankshaft which lined up with the old belt marking

 

Do I leave my cam sprockets where its at lined up with all the marks and crank the crankshaft by hand clockwise till i can get it to line up with the new belts 43dr tooth mark?

 

Thanks fellas WAVEY

Link to comment
Share on other sites

Moving the cams a tooth or 2 won't hurt anything but if you leave the cams where they are and rotate the crank you'll squish valves against pistons and it doesn't take much to warp a valve to the point of no compression (been there done that) the only safe way to turn the cams or crank with the engine assembled is to remove the rocker arms that way none of the valve are open.

 

If you're only off by a tooth you can safely move the cam to where it needs to be. Just don't move the crank too much and triple check everything after you have the belt tight. Just remember that the dimples on the upper timing covers are more of a guideline and counting the teeth on the belt is the only reliable and foolproof way to know you've done it correctly.

 

Sent from inside my potato

Link to comment
Share on other sites

Just remember that the dimples on the upper timing covers are more of a guideline and counting the teeth on the belt is the only reliable and foolproof way to know you've done it correctly.

 

Sent from inside my potato

Definitely.

 

I just did mine and the teeth count was accurate but the cam backing plate marks were about a tooth off in each direction.

 

 

Sent from my iPhone using Tapatalk

  • Like 1
Link to comment
Share on other sites

When the engine in my pathfinder gives up I'm going to swap in a Vg33 from a quest or villager so I have the larger displacement plus the deeper valve reliefs in the pistons so if the belt ever does break I can just spin everything around slap a new belt on and be on my merry way lol

 

Sent from inside my potato

  • Like 1
Link to comment
Share on other sites

When the engine in my pathfinder gives up I'm going to swap in a Vg33 from a quest or villager so I have the larger displacement plus the deeper valve reliefs in the pistons so if the belt ever does break I can just spin everything around slap a new belt on and be on my merry way lol

 

Sent from inside my potato

what are you going to do about the crank pulley???

Link to comment
Share on other sites

The vg30 crank will swap right in, basically the only difference between the 30 and 33 are the cams, crank, oil pump, and it's accessories like ac and power steering. The rest will fit. You can take everything from a vg30 and bolt it to a Vg33 block. There's a ton of info here on NPORA about it, just search Vg33 swap and have your mind boggled from everything.

 

But what I really want is the Mr.510 crank adapter that he made so you can use a Vg33 crank with all the vg30 accessories.

 

Sent from inside my potato

Edited by RCWD21
Link to comment
Share on other sites

there is a difference in the diameter between the 3.3 and the 3.0 you could swap the 3.0 crank over.

Mr 510 isn't making them anymore I know I tried to get one.

I ended up using parts off a 2000 exterra, oil filter base, alt and A/C comp, bracket Ps mount and pump.

you could find a machine shop to turn the 3.0 pulley out to fit the 3.3 crank that would be about the cheapest way to go.

you could try and get in touch with my1path think he still has a connection with Mr. 510 maybe get him to turn out a few more

Link to comment
Share on other sites

Moving the cams a tooth or 2 won't hurt anything but if you leave the cams where they are and rotate the crank you'll squish valves against pistons and it doesn't take much to warp a valve to the point of no compression (been there done that) the only safe way to turn the cams or crank with the engine assembled is to remove the rocker arms that way none of the valve are open.

 

If you're only off by a tooth you can safely move the cam to where it needs to be. Just don't move the crank too much and triple check everything after you have the belt tight. Just remember that the dimples on the upper timing covers are more of a guideline and counting the teeth on the belt is the only reliable and foolproof way to know you've done it correctly.

 

Sent from inside my potato

Thanks for the quick and very informative reply RC.

 

I did move the cams earlier ( cranked it clockwise)and the crankshaft mark lined up to the 3dr line on the belt without moving the crankshaft no problem. both L3 and R3 cams are not lined up with the dimple on upper timing plate by a tooth but like you mentioned its fine. Adjusting the belt tensioner would be different also, the allen hole is not going to be at 4 anymore. Is it ok as long as the belt has about 75-80 degree twist?

 

Everything is lined up now as far as the cam sprockets indents to the lines on the belt at 40 teeth from R3 to L3 and 43 from L3 to crankshaft. Glad I posted before I started cranking that crankshaft to make it line up with the 3rd line on the belt, you saved me some big bucks there

 

Im just puzzled why the original belt lined up with everything perfectly. When I removed the cam sprocket I put a couple of zip ties on the old belt to the sprocket and used a impact gun and got the bolts loose and those sprockets didnt move and all lines are still lined up with the dimples and indents. I was being very careful throughout this project and took my time. After getting the cam sprocket out theres no way that those cam shafts are going to move even the crankshaft is there?

 

Anyways thanks for the help and will triple check tomorrow before I fire her up

Link to comment
Share on other sites

They will move due to the insane amount of pressure from all of the valve springs and them wanting to find a happy medium.

 

I don't take any sprockets off, I just loosen the tensioner bearing nut (not sure if you're referring to that as a sprocket or not) but as long as the lines (make sure the belt is on the right way as most of the ones with the lines have a band of arrows that are more like a line of triangles that point out its proper orientation) line up with the dimples on the crank and cam sprockets. As long as the belt is on correctly and the lines line up you'll be ok.

 

Also, it says to twist to 90° but honestly I think as long as it's close to that it'll be ok.

 

Did you replace your water pump while you had the belt off? That's usually common practice but not do or die. It just really sucks to do a belt and have a water pump go bad or start leaking and getting antifreeze all over a new belt which causes the belt to deteriorate which could allow it to break at some random point.

 

Sent from inside my potato

Link to comment
Share on other sites

Does anyone know what kind of clearances are between the valve/pistons? When I did mine last week I slowly cranked it over with a rachet and all plugs removed. It's turns very easy with minimal resistance, so I would think you could feel if the valves/pistons meet depending on how far their respective strokes cross over? Isn't that the whole point for why it's recommended to remove the plugs? I set it at tdc before removing the old belt with the plugs in. It was a little harder to turn over but didn't end up being an issue.

 

 

Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

They will move due to the insane amount of pressure from all of the valve springs and them wanting to find a happy medium.

 

I don't take any sprockets off, I just loosen the tensioner bearing nut (not sure if you're referring to that as a sprocket or not) but as long as the lines (make sure the belt is on the right way as most of the ones with the lines have a band of arrows that are more like a line of triangles that point out its proper orientation) line up with the dimples on the crank and cam sprockets. As long as the belt is on correctly and the lines line up you'll be ok.

 

Also, it says to twist to 90° but honestly I think as long as it's close to that it'll be ok.

 

Did you replace your water pump while you had the belt off? That's usually common practice but not do or die. It just really sucks to do a belt and have a water pump go bad or start leaking and getting antifreeze all over a new belt which causes the belt to deteriorate which could allow it to break at some random point.

 

Sent from inside my potato

I took the cam sprockets off to change the cam seal. The belt has lines of arrows towards me installed

 

I replaced the water pump tensioner and thermostat also and the PITA bypass hose thats originally the reason why Im doing this and its probably a good thing that that bypass hose leaked because when I removed everything the belt is loose as a goose and probably ready to break. Im going to triple check everything in the morning and keep you guys posted on the result.

 

Would it be OK if the allen hole on the tensioner is not at 4o'clock ?

Edited by PATHRIDER
Link to comment
Share on other sites

That little hose is fun isn't it? I don't think anyone on this forum like it's haha

 

And it should be fine as long as the belt it tensioned correctly, I usually just try to get everything as close as possible to what the book says. With the belts I've used some felt overly tight when it was at the 4 o'clock position so I put it where I felt comfortable and have never had a problem.

 

Sent from inside my potato

Link to comment
Share on other sites

RC sorry for the late update. Got her running smooth yesterday with no accessories hooked up like the alt, water pump , ac etc and it fired right up with a nice throaty sound to it (3 months old muffler)

 

This morning I was going to wrap everything up but had a hard time getting to one of four of the stud on the fan clutch that is dead center underneath to screw in the nut so I decided Id bump it , looked at the stud and its in the same place so I went and bump it again and still in the same spot. Decided to crank it and loud squeling noise so I turned it off right away thinking its the alternator, pulled it and had it tested and it checked ok so went back home and checked under the hood again and it dawned on me why that fan clutch didnt move a bit when I was tightening the 10mm nut and I remembered when I did my pathy that when I was tightening those 4 nuts it would move a bit thats how I was able to get to all the stud and screw in the nut with no problem because if I crank enough on it it keep spinning the pulley to where the other stud would be easily accesible on top.Tried to spin the water pump and it wont move at all. Never thought it would be it because it is brand new and I checked it before installing it. It seized and I have no clue why it did that

Im pulling it out tomorrow and get another one at motion where I usually get my parts once in a blue moon.The pump I used is from autozone and I dodnt know why I went there in the first place :headwall:

The dealer has a 4 day wait at the time I did this project and I need the parts right away so I can drive my truck to work

 

Another thing on the tensioner, I ended up not using the spring because it is to far to even catch on the stud, The allen hole is at eleven o clock and its perfect. I just dont want that spring flopping inside and maybe the part that catches on the stud might get caught on the belt, it is really loose

 

Heres a few p;ics where the lines on the belt ended at. It was a tooth off to the right of the backplate dimple but after tensioning it it is now on the left

unnamed.jpg

unnamed_1.jpg

unnamed_2.jpg

unnamed_4.jpg

Edited by PATHRIDER
Link to comment
Share on other sites

Ok after doing some more thinking I think that when I installed the water pump yesterday some of the water that froze in the piping somewhere drained to the water pump cavity when it got warm here and with the pump sitting overnight in 17 degrees temp it froze again freezing the impeller. Can I put a heat gun to it like how I melted some of the ice inside the tstat housing?

 

Ive been putting water on the rad because its just leaking on the bypass hose anyways and figured Ill fix it soon but didnt expect well suddenly have a freezing temp. All my fault :(

Link to comment
Share on other sites

  • 2 weeks later...

Sorry for the late reply fellas, the snow just wont let up and finally got some 30 degree weather here and finally was able to finish it

Adamzan I replaced the bypass hose and that was the original problem

Now the truck runs so smooth but with one major problem maybe (hope not). I might have ruptured a hose somewhere underneath the intake manifold and it was just leaking like crazy underneath there. Its either a hose or the tube that runs to the back of the motor. I believe it is connected to the back of the thermostat housing, When I was doing my water pump, timing belt and bypass hose I noticed that that pipe that runs in the middle of the engine underneath the intake manifold is just just frozen solid thats why I waited for a nicer weather for it to thaw out but I guess I must've screwed it up last week when I first finished the timing belt and decided to start her to see if I did the timing belt right without the radiator hooked up but it would have not mattered anyways because I already noticed the leak from the water that got thawed. I thought maybe its just frozen water from the bypass hose leak and it melted when the engine warmed up but its not

Any input is greatly appreciated guys

 

Have a Merry Christmass all

Link to comment
Share on other sites

You could use a heat gun to thaw out any frozen water but another thing you could do for over night waiting periods is put a drop light under the hood itll help keep things from getting totally frozen depending on how cold it gets. Also make sure there is antifreeze in the cooling system and not straight water. If it's still sitting with water I'd go ahead and drain the cooling system to get as much as possible out and pour in some antifreeze.

 

There are a few spots in the engine valley that could be leaking. One is right under the bypass hose where the metal pipe bolts in. There's another spot at the back of the block where it turns and runs to your heater core.

 

There's a few rubber hoses that are on the intake manifold that could be the issue too, make sure your clamps are on and tight and if they're questionable go ahead and replace them.

Link to comment
Share on other sites

Thanks RC. I checked the pipe under the bypass hose and the end of that pipe that flanges to a 45 degree bend pipe to the heater core by the firewall and close to plug 6 and no leak.

Im going to pull the intake off and see what I can find underneath. Its been a crazy winter here and too cold to be working in the carport.,hoping we get some decent weather atleast in the 20's and Ill pull that intake off. Done an injector swap on my pathy long time ago and IIRC its not so hard just time consuming

 

 

Have a Happy New year :beer:

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...