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Demon I Am
08-07-2012, 03:54 PM
I am installing a 1996 1.8 into a 1990 Miata. I have a few weeks before the actual swap, and have been doing as much preliminary work as possible. I am in process of installing the new Timing Belt and have run into two issues. I searched M.net for info, but actual info was hard to find through the E-penis contests, and outright wrong info.

1. The cam gears were removed before I received the engine, with no marking as to the original positions. I installed the new water pump, cam seals and pulleys, however, the pulleys do not "rest" on any of the I/E markings. When you turn a cam, it "rests" on 1 of 4 positions. The closest I get leaves the intake side "E"s about 2 teeth away from the alignment mark (withe the primary cam lobe facing the fender). The exhaust side "I"s are about 1 tooth shy. Is this where I need to manually set both and clamp the crescent wrenches together (or get an extra set of hands)? The cams have enough tension on them, that I can't hold both in place and slip the belt on. I just want to make sure I am installing everything correctly.

2. I have my crank pulley lined up properly, but to do so, I had to rotate it, via the boss bolt. When I do this, it starts to go 1/4 turn, and then gets suspiciously hard to turn. I did not want to put any more pressure into it, as the boss bolt started treading in instead of turning. Any clue what might be going on?

ctrench
08-07-2012, 04:18 PM
dont qoute me on this, but this is from my own experience...

1. you need two wrenches and a c-clamp to hold the cam gears in the right position... and as you said the gears "rest" in one of four positions due to the combustion cycle.

2. when you turn the crank the pistons are creating pressure in the combustion chamber making it harder to turn, dont worry about the bolt threading in, once you get the belt on, it will give you enought tension to reverse the bolt back out


edit: please dont take this the wrong way... but im surprised you are attempting a 1.8 swap without knowing about this procedure, and not knowing about the crank bolt being hard to turn due to you creating pressure from turning the crank

Demon I Am
08-07-2012, 04:43 PM
This is not my first timing belt job (or motor swap), but it is my first with a "new" engine, not installed in a car. If you never did anything for the first time, you would never do anything at all.

I figured the crank issue was pressure, but read some Mnet stuff about not turning the crank if you feel anything more than minor resistance. Something about the pistons touching the valves, if the cams are in the wrong position.

ctrench
08-07-2012, 05:16 PM
ok its all good, i was just checking... and miata motors are non interference, you cant hit any valves

Demon I Am
08-11-2012, 09:43 AM
All good now, This motor is almost ready to roll/rotate!

ctrench
08-11-2012, 10:40 AM
nice!! did it go back together easy?

Demon I Am
08-11-2012, 11:39 AM
Oh yeah, just needed the right tool. Vice clamp TFW

tsingson
08-13-2012, 11:30 AM
So whats the plan for getting this in? Did you speak to Mikael about scheduling a time to get this done?

93miatale
11-25-2012, 10:33 PM
being the cam gears where off when you got it, it's rather easy to make sure it's right. Just make sure the cams are pointing outwards from the car east and west. You can also use two crescent wrenches to hold the cams in place and some vice scripts to hold them together and the cams wont turn. Just make sure the crank is pointing up when you put on the belt. you can at least get it either even or a tooth or two off and timing it from here is rather easy.