1997 ti M-sport, M44 5-sp. M3 front suspension, with L/R swapped strut guide plates. 140K miles
Before:
After:
So my M44 was leaking oil and coolant, which looked like it was coming from the head gasket area. Lots of moisture on the passenger side of the block. I was seeing about a tsp of fluid on the ground after every park.
I had my suspicions that the oil pressure baffle / relief valve on the oil filter housing was going too. I went as far as starting the procedure for an oil filter housing gasket replacement (found here link), and got down to the housing itself when I noticed the moisture on the other side of the block as well. I just decided to stop at that point, and search for another M44.
I came across an M44 from forum member (
318ti Ghost), with 64K miles on it. Dry block, no leaks!
Change directions here and talk suspension. I have M3 struts, Ground Control springs, with M3 guide plates, which were swapped L/R for additional camber and caster. Solid control arm bushings. Real stiff setup. Note: M3 strut guide plate reinforcements were NOT installed. This, ultimately, may have been the cause of the failure. Due to the added stiffness of the M3 setup, plus the difference in where these forces are applied with reference to the stock strut location, cracks were developing in the stock shock tower. (stock struts come up centered in the bore of the strut tower, M3 setup with L/R swap is inboard and rearward of the stock location)
Now I had noticed this crack before, but it was only about ¾” to 1” of separation at the time. I figured I would have to deal with it eventually, but that it was okay for the time being. Much to my surprise, the crack was accelerating. 3” of separation, from the inner upper bore of the shock tower, near the inboard mount stud. And on both towers, the inboard mount stud was angled inward, indicating flex and failure of the guide plate. Sure enough, even the guide plates were cracked in these same spots.
Fortunately for me, (
318ti Ghost)’s brother Scott wasn’t intimidated by this, and immediately suggested a reinforced upper plate be fabricated and welded in. Initial discussion also involved an inboard reinforcement section, but upon later analysis, it was determined this wouldn’t necessarily benefit the ti shock towers’ conservative inboard lean angles. We will, however, be adding a custom strut bar for further reinforcement.
The repairs took a few days, one day for measurements, another day for fitting and me receiving instructions on how to prepare the surfaces, another two days for welding.
Unfortunately, my garage didn’t have a 220V hookup, and we only have one hot line coming in from the street, so I had to rent a generator that supported 220V for the MIG welder. With some clever scheduling, I was able to only pay for one day of rental ($70).
After the repairs were complete, I primered and rattlecanned it with Krylon rust-tough semi-flat black. Matches the non-clear coated BMW Schwartz of the engine bay pretty darn well. Had left over half-cans, so I sprayed my kidney grilles while I was at it.
Installation is reverse of removal!
M44 – 64K miles. Fresh Sachs clutch, full kit from Pelican parts. Mangled one of their fancy $50 pilot bearing puller tools in the process – word of warning – just go buy a slide hammer with hooks from harborfrieght for $17. Wayne at Pelican was cool, and refunded me for the tool. I sent him the old bearing to show that it wasn’t scuffed on the outer bore, or rusted, or anything. It wasn’t even in there very tight, it’s just the cheap metal in their tool buckled. He says the quality has been going down.
New T-stat housing, rear block coolant fitting, main block coolant fitting, swapped in water pump from my old engine (only had 30K on it) with new gasket, handful of other new gaskets here and there, and other various clips, nuts, bolts, etc.
I’m proud to say that there is only one broken or missing OEM clip in my engine bay – the A/C line retainer clip that ties in to the passenger shock tower. EVERY other freaking plastic clip or attachment is OEM complete! It’s like a dream – no sounds at idle, everything is nice and clean. Feels like I just completed a giagantic fracking hobby kit out of the realoem.com ‘fiche pages.
The only item of note on the 64K block going in -- when I pulled the water pump, there were some deposits in the cooling circuit. Looks like someone was either using standard glycol with phosphates, or tap water, or something…. Crusty buildup that scratches off with your fingernail, and can be ground down into powder between your fingertips. Cooling system is therefore due for a flush because of this.
I even managed to replace a few missing screws from the valence area and wheel wells, helping secure my front bumper better than ever. It feels SO SOLID now. It’s such a rewarding feeling.
So, if you have any questions, or would like further information, please let me know. I can happily say that I have personally torqued every fastener I got my hands on to factory spec, and I have to say – the Bentley manual was a huge savior here. Aside from a few torque values that aren’t published, I was able to figure everything out with its help.
The best part of all – after 5-6 seconds of pumping gas back into the rail, the motor fired right up and ran like clockwork. After briefly bleeding the coolant circuit, I was off tearing up the streets. Did I mention how SOLID everything feels!
The old M44 will be drained, disassembled, bagged, and put into storage for a build project next summer. Haven’t decided what to do with it yet.
Cheers!
tbw
(the blonde weasel)