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I had no intent of slamming vendor I was going to call and have them verify the dims you gave me to another one they have on the shelf
Problem is vendor and ATI are out of stock, Friday they were to pull technical drawings to compare...I have not heard anything, I'm trying not to get angry...
This might sound like a stupid question... Did you put the quide plate on the end before you installed it? Otherwise, the damper would sit too far back.
Pic of mine for reference [and the step height is 22.49, exactly the same]
This might sound like a stupid question... Did you put the quide plate on the end before you installed it? Otherwise, the damper would sit too far back.
Pic of mine for reference [and the step height is 22.49, exactly the same]
yes I did and the guide took some time wiggling it to remove because the roll pin is rather tight
This might sound like a stupid question... Did you put the quide plate on the end before you installed it? Otherwise, the damper would sit too far back.
Pic of mine for reference [and the step height is 22.49, exactly the same]
how thick is your trigger wheel?
as you can see mine is 2 mm
1.858 according to my micrometer. Close enough....
I think if you look at most 1.6 or 1.8 engines the timing belt sets back towards the back on the cam pulleys instead of in the middle of the pulleys.
I have a 1.6 in the driveway and it sets just as far back as the 1.8 with the factory damper
I think if you look at most 1.6 or 1.8 engines the timing belt sets back towards the back on the cam pulleys instead of in the middle of the pulleys.
I have a 1.6 in the driveway and it sets just as far back as the 1.8 with the factory damper
Not sure your point. My "close enough" comment was in reference to the difference of my trigger wheel vs. yours. Difference = 0.072mm or .0028"
Unless you left off the rear plate/guide and let the damper move back on the crank snout I don't see how the damper is the issue especially accounting for the pics. You're installing on a 1.8 right?
Not sure your point. My "close enough" comment was in reference to the difference of my trigger wheel vs. yours. Difference = 0.072mm or .0028"
Unless you left off the rear plate/guide and let the damper move back on the crank snout I don't see how the damper is the issue especially accounting for the pics. You're installing on a 1.8 right?
(1) 1.8L Miata crank snout with the particular surfaces noted EDIT: WRONG DIMENSIONS IN 1ST PIC. Ř45 SHOULD BE Ř36.5
(2) ATI damper as assembled ready to go on. Note some relevant dimensions which would mean the surface the damper would push against [thrust] is marked with an "X"
EDIT: MATING SURFACE IS NOT THAT MARKED WITH "X"
(3) EDIT: PIC REMOVED
Like I asked before, are you sure you had the rear guide on the damper when you assembled it on the crank?
(1) 1.8L Miata crank snout with the particular surfaces noted
(2) ATI damper as assembled ready to go on. Note some relevant dimensions which would mean the surface the damper would push against [thrust] is marked with an "X"
(3) ATI Damper with the rear guide left off, again with some relevant dimensions. Note, the counterbore of the timing belt hub is larger than the crank oil seal diameter. This would allow the damper to locate further back locating on the surface marked with "X" making the timing belt look further back. The actual change would be 5.75 +/- [.226"] which is the thickness of the rear guide + the depth of the timing hub counterbore.
Like I asked before, are you sure you had the rear guide on the damper when you assembled it on the crank?
I will say this again yes
I know this because before I took those photos (after I pulled the damper off the crank) I pulled this guide off and it was a PITA because the roll pin is very tight so I had to wiggle this plate for about 5 minutes and slowly it came off...
I will say this again yes
I know this because before I took those photos (after I pulled the damper off the crank) I pulled this guide off and it was a PITA because the roll pin is very tight so I had to wiggle this plate for about 5 minutes and slowly it came off...
Is this a built engine? Is it possible the thrust washers are not in there allowing the crank to move back and forth? I know you installed the OEM damper and the belt aligned fine, but the crank could have moved.
I follow bahurd's logic in that if the rear guide is on, there is no way for the belt to move that far back...unless the whole crank is moving.
Is this a built engine? Is it possible the thrust washers are not in there allowing the crank to move back and forth? I know you installed the OEM damper and the belt aligned fine, but the crank could have moved.
I follow bahurd's logic in that if the rear guide is on, there is no way for the belt to move that far back...unless the whole crank is moving.
--Ferdi
I checked all tolerances of this engine and put them in an Excel spreadsheet
the thrust bearing tolerance is 0.007" for this engine.
OK I just noticed something, according to your dimensions the step up on the crank shaft does not fit inside the 39.05 mm Dia. depression because that part of the crank shaft has a 45 mm Dia.
when I installed the damper the roll pin was sticking up and according to the Fab9tunning video this pin will be pushed in when you install the damper,, which is what happen because it was pushed in when I pulled the damper off.
Originally Posted by bahurd
OK, here's some pics;
(1) 1.8L Miata crank snout with the particular surfaces noted
(2) ATI damper as assembled ready to go on. Note some relevant dimensions which would mean the surface the damper would push against [thrust] is marked with an "X"
(3) ATI Damper with the rear guide left off, again with some relevant dimensions. Note, the counterbore of the timing belt hub is larger than the crank oil seal diameter. This would allow the damper to locate further back locating on the surface marked with "X" making the timing belt look further back. The actual change would be 5.75 +/- [.226"] which is the thickness of the rear guide + the depth of the timing hub counterbore.
Like I asked before, are you sure you had the rear guide on the damper when you assembled it on the crank?
OK I just noticed something, according to your dimensions the step up on the crank shaft does not fit inside the 39.05 mm Dia. depression because that part of the crank shaft has a 45 mm Dia.
when I installed the damper the roll pin was sticking up and according to the Fab9tunning video this pin will be pushed in when you install the damper,, which is what happen because it was pushed in when I pulled the damper off.
I guess I should know not to use "internet" dimensions.... sorry.
I just went out to the garage and measured my engine and the corrected dimensions are below. So yes, the seal diameter fits into the counterbore and it changes where the mating surface is. Other than my pic being wrong I'm not sure what that resolves without measuring the factory setup and comparing. You have both so you can do that. Right?
I'll try and find my factory damper and timing belt hub.
The picture has the relevant measurements for both ATI and the NB timing belt hubs insofar as how/where they mount on the crank. I guess we both agree the mating surface for both is -A- as I marked on the picture. Right? With the thickness of both as noted, the front surface of the belt guide would be placed in relation to the mating surface; ATI = +0.33 vs Stock +0.22 . In simpler terms, on my crank the ATI is 0.11 [.004"] further ahead than the stock guide and well within the OEM tolerance I expect. Surely not enough to account for the difference in your earlier picture. So I'm sure this doesn't help with WTF is the issue but it closes the loop on my earlier messed up data.
01-09-2018, 01:18 PM
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