...something that would not budge, causing it to explode in a shower of brittle yellow plastic pieces all over the engine compartment and my garage.
So, finally got my car reassembled enough today to try starting it. It started, ran for 3 seconds and I cut it off because this happened. I'll take everything apart do a postmortem but I can tell you I was absolutely sure the fan was not contacting anything when I assembled it. Yes it was very close to the breather coming out of the timing chain cover but there was clearance there. I'm thinking the fan flexed once it got some rpms and then decided he didn't like the breather all that much.
Ouch! I hope you were not hit by any of the flying pieces.
Nah. I was sitting behind the wheel starting the car. So, happiness that the car started on first try lasted for about 2.5 seconds. ;D
Bummer:
my bet is an dropped wrench or screwdriver into the shroud = forgotten about
Ive Been there done that myself... Happens
Hopefully nothing wrecked the rad either.
The soft aluminum (brand new!) radiator took some hits, but is not showing any leaks. Yeah, could be user-error like a screwdriver. I'll find out.
By the way, this was a brand new fan. But it was the non-genuine fan (as MS calls things). I think the original OEM yellow plastic fan might have just bent instead of exploding. Something to think about when ordering a new fan
Well, I tore it down and there was no dropped bolt or misplaced screwdriver that caused the fan to explode. Although it did not touch the breather when I spun it by hand during assembly, it seems that it barely hit the breather when the engine started as I thought. So it must have flexed just that little bit when it got spinning at engine speed. And as soon as one blade broke it hit another blade and started a chain reaction I am guessing. The "non-genuine" fan really is made of cheap nasty plastic - the savings can't be worth it over the genuine article.
I'm not exaggerating when I say the cheap fan broke up into at least 30 different pieces - found one piece about 15 feet from the car on the other side of the garage. The aluminum radiator seems okay, but I'm going to reinstall the old 2 core radiator and the metal tropical fan I pulled out 2 months ago. That combo has worked well in the heat and the metal fan is too thick to use with the thicker aluminum radiator.
Interestingly enough my aftermarket new fan barely nicks the breather on a couple blades on the tips. I just assume it will wear itself down but maybe an explosion is in my near future too. You had the spacer in place?
Was the fan installed the correct way around?
Quote from: 94touring on September 14, 2018, 06:23:26 PM
Interestingly enough my aftermarket new fan barely nicks the breather on a couple blades on the tips. I just assume it will wear itself down but maybe an explosion is in my near future too. You had the spacer in place?
Yup. And I even fitted a washer for each bolt between the pulley and the spacer just for another 16th of an inch as extra insurance. Next time I think I would consider gently profiling the tip of the fan blades if they were that close.
Quote from: Scargo on September 14, 2018, 06:36:50 PM
Was the fan installed the correct way around?
Yes, I was careful to make sure of that.
On the bright side you're getting really good at working on the cooling system.
Fyi Bruce, go get yourself a long flat head screw driver if you don't already have one. I grabbed one from harbor freight that's about 2 feet long. Makes the lower rad hose clamp very easy to tighten.
Quote from: 94touring on September 14, 2018, 08:59:59 PM
On the bright side you're getting really good at working on the cooling system.
Haha. Very true. I've done about 4 radiator installs and removals over the past several days. Lots of do-overs for one reason or another.
I've got a BF screwdriver that I use for that - but thanks for the advice.
I use some silicone lubricant paste on the hoses, they go on and come off easily then, even years later. I also use screw clamps with a hex head on them, then a 1/4 drive socket and long extension makes it easier to do and undo the clamp
Having seen my share of turbine blade fractures I would say that BruceK is right that it is knockoff from hitting something (breather tube apparently was closest). Plastic being flexible the airfoil will untwist from the root when accelerating with the aero loading. Curiously, with the fan on "correct way" slightly increases the twisting load. A reversed fan would have less twisting due to fan speed but probably not enough to prevent "explosion"
It will also lean forward i.e. towards the engine under aero load further exacerbating the breather clearance.
Plastic usually are very flexible and flexure in this case is the enemy. If I were going the plastic route I would check flex and get the very stiffest you can find. The steel fans will have very little aero flex at the relatively slow engine speed compared to an axial flow turbine engine speed.