jdogg
Reader
7/4/21 4:11 p.m.
Post a video of the noise when you can, GRM's Probe demi-god has arrived.
There are typically one of three things that cause a tapping noise on these Mazda V6 engines. The first is the tensioner, which is actually a fairly easy fix as is the timing belt job on this. Do the water pump while you have it all apart. Don't use those plastic tensioner pulleys, they will separate and then you're in big trouble. The KL is not an interference engine though, so you're good there.
The other two are a lot more intensive and happen as these engines age, and those are the HLA's and the friction gear spring on the cam shafts, which those two are rare and happen if you don't stay on top of oil changes. The HLA and FGS usually go away after 2500 rpm and they aren't dealbreakers but to fix them you're looking at a cylinder head rebuild which these heads are cheap just get remans from ebay.
While you're at it, if it turns out to be the last two, consider upgrading to the solid lifter head from the KLG4 which is the later model KL found in the 98+ 626. They also have a different intake manifold which makes serious power on the KLDE when paired with either Megasquirt or a MAF conversion kit. It is a direct bolt-on to the KL block and you won't make any more power on them but they are drastically more reliable. And while you're at it, find a set of KLZE cams, you can buy mine if you need them after I finish building my KLZE. They push the power band up a bit for top end power and when combined with the KLZE manifold it's a 20hp gain across the board.
The big reason you want to do the MAF conversion is to fix the power curve, past 4500 rpm the ECU can't read the VAF so it just dumps a ton of fuel and the curve dips right before VRIS engages. The MAF conversion smooths out the curve and combined with the G4 manifold which is readily available in any junkyard the gain is 18-22hp mid range and it's definitely noticeable out of corners. Find a MAF conversion on the various Facebook pages for these cars, they do trade hands often. I went to full Megasquirt standalone.
In reply to jdogg :
I think I recorded this video a year ago but nothing's changed since then since the car's been sitting since fall. I leaned in towards the belt area because it seemed like the sound was coming from there, but I could be wrong.
jdogg
Reader
7/9/21 10:04 a.m.
That's 99 percent the tensioner. It's hydraulic and over time it collapses after 20 years.
Almost seems like you can see it jumping around in time with the sound.
Yep, 99% sure that's the TB tensioner. my 96 PGT started making that sound at 142k miles. Seal goes bad, oil leaks out (no more damping), makes clacking noise like cracked piston or loose skirt clearance.
I'm wondering if I should even bother with a standard-style replacement, or if I should get something like this King6fab adjustable tensioner and remove the potential failure point of the hydraulic bits.
https://www.king6fab.com/product/adjustable-timing-belt-tensioner/
In reply to slowbird :
How many more years / miles are you gonna put on it? I mean, your original worked for 15 years...
In reply to AngryCorvair (Forum Supporter) :
The nineties were two decades ago. Time flies when you're old.
In reply to AngryCorvair (Forum Supporter) :
The original worked that long, but I don't know if they make replacements up to OEM standards anymore...
Plus, custom-fabricated thingy = "race car" = cool
Swapped the wheels around so the big ones are on the front and the stock ones are on the rear. To avoid the different diameters on the drive wheels, and such. This required briefly putting a different tire on the right front so I could take that tire and move it to the left rear. As such, here is a Lincoln Town Car wheel temporarily propping up a Ford Probe.
I thought the tire would be too big, but it was ok. Might rub if actually used for driving. But yeah, it doesn't look too bad on there. If this thing was stock height I think I would put these wheels on with decent snow tires and take it rallycrossing.
Also I found a battery at Walmart that should work and is only $89. I didn't buy it yet but when payday rolls around this puppy is getting fired up and driven halfway up the driveway with a new battery so I can use it to try and jumpstart the Cougar's dead battery. Then it will also be functional enough to motivate me to try and do something about the belt tensioner and get it inspected and road legal again. And then maybe get some decent tires for the Mustang wheels so I can autocross it. Maybe. Someday. If I can stop spending money on other E36 M3.
jdogg
Reader
7/26/21 1:49 p.m.
In reply to slowbird :
My tensioner I did on my KLZE build was a new one from Autozone (Duralast) and it has lasted 10k miles with no shortage of 8000 rpm abuse in between.
In reply to jdogg :
Good to know. Maybe I'll just go with one of those then. Speaking of which, it's definitely time to get to that soon, because I put a new battery in and drove around the block today. But first, I couldn't get the clutch to release, which was not a problem the last time it ran. I checked the shared brake/clutch reservoir and it was below the top, but not by a lot. I topped it up anyway, then tried pumping the pedal and also pulling it up with my foot until it quit sticking. Success!
I forgot the tach doesn't work. I also really need new tires because these ones are trash even though they hold air, and four matching ones would be nice. I'm not sure if the vibrations were from rock-hard rubber or the wheels having a slightly larger hub bore than stock. I think I can find hub rings in aluminum; I misplaced the plastic ones I bought previously. I need to fix the right headlight, make some foglight brackets to replace the missing ones, and replace a few missing nuts and bolts. Also, new pads and rotors might be a good idea. And the airbag light might be a problem...
And all of that while still trying to book a hotel for an upcoming rallycross with the Focus. And also trying to buy parts to fix up the Cougar. Sigh. My ambitions outpace my means.
Right, so, RockAuto had a single solitary right side headlight motor in stock, so I figured I'd better get it. Mostly because that's the side that stopped working a while back. It would kinda work, slowly, for a while. Gradually getting worse and worse, until it finally stopped entirely.
I installed the new (remanufactured) motor today. Headlight still won't pop up. No idea why. I'm not a mechanic, just a parts replacer. I will research it some more I guess. And then probably give up and take it to a shop.
Side note, I hate working in the garage because it's gross. So many bugs get in and I saw a huge nasty spider today. Freaks me out. I would like to have a bug-free work space someday.
jdogg
Reader
8/12/21 8:08 p.m.
In reply to slowbird :
Headlight motors are controlled by I believe either a single relay or one for each motor. Check the connector also for corrosion, these are 30 year old cars after all.
Clutch, they do that sometimes, check the clutch master cylinder for a leak, it has it's own cylinder and the top of it is plastic and they leak on reman units sometimes.