December 2010

Since the urethane added to the mount was only cured for 40 hours when I test drove the Insight today, I was a bit nervous that it would not be cured enough to withstand the test drives. But it worked. It does not respond so harshly to having a chattering clutch with the motor mount repair/improvement that I made with the Loctite Urethane from Home Depot. I tested the worst case situation for the motor mount over by my mail box. The driveway there is a bit steep. I usually have to back out of it going up hill. Backing up this hill made the engine shake thunderously due to the worn out rear motor mount. But now it feels as though the clutch is still chattering, but the whole engine and chassis are not responding to the chattering any longer. I could back up the Insight at far lower rpm and still get a fairly smooth motion out of the car considering the clutch chatter. Now the test will be to see how long the urethane mod lasts. The cure time is 7 days. I’m hoping that setting it to cure under a 100w incandescent lap helped to shorten the cure time. In fact the lamp browned the white urethane just a little on the surface. The center bushing and the mount itself was quite hot after sitting over night under the 100w bulb. Those inefficient bulbs sure make for easy curing ovens. So I think this repair/mod of the rear motor mount was a worthy improvement for general reasons, but specifically for helping tame the clutch chattering so many of us have. I knew the mount was stiffer as I could not tilt the engine up and down with my hand while laying under the car. It was located far more firmly. I could not tell that any more vibration was added to the chassis by making this mount a little stiffer. The car still feels smooth and quiet as far as vibrations are concerned.

The car seems smooth on acceleration since I’ve cleaned out the egr plate. I’ll still swap out the egr valves to see if they produce any noticeable change in driving feel. I also put a bunch of missing screws back into the under chassis aerodynamic panels. They cost a bit from Honda.

I saw that there was some room for a screwdriver to pry the crankshaft dampener away from the engine to help check for end play. Pushing the crank back in will be tougher.

The fuel rail washers went in today. No more fuel leak.

Here is the rear motor mount with Loctite Polyurethane PL Window, Door and Siding Sealant from Home Depot. I found a post in a Honda-Tech thread that a guy tried it and liked it’s vibration isolation characteristics better than the 3M Window Weld Urethane. The bridge added to the top section should really help the clutch chattering when in reverse. I made the repair late at night. Too late to notice that the urethane was white instead of black. Gray is the closest color they offer to black.

A few things I found out tonight working on the Insight.

There is not an inspection panel to check the crankshaft end play. The oil pan would have to come off. The oil pan is clear of any obstructions, but it has the oil filter and something else attached to it. Decisions, decisions.

Here is the rear motor mount from my MT Insight. The mount is pictured just like it sits in the car. The broken leg points toward the front of the car, the good leg towards the rear, and the short leg points upward. The lower right leg is cracked clear through. Both lower legs are compressed when the car is in any forward drive gear. That means the lower legs are stretched when in reverse. With a broken leg the motor mount will not dampen the engine when in reverse. I was thinking of taking some of that Urethane window caulking called 3M Window Weld and gluing the broken leg back into place, but more importantly adding a bridge from the top leg to the inner ring. That will help the reverse gear chatter and help hold the broken leg in compression and hopefully make it a bit more stable. A new mount is about $80-$100USD. So a tube of Urethane and some time is a good trade off. The motor and trans are balanced well so that the rear mount being removed does not require anything to hold the motor in place.

Egr function is about volume of flow. A small reduction in cross sectional area creates a large reduction in the volume of egr gas flow. So I suspect these egr plates need to be kept clean for this super high performance Insight engine to do it’s job at 80-100mpg.

I ended up touching up the egr plate with q-tips and carb cleaner. The carbon is so dense and sticky that using the small screwdriver to get 99% of the carbon out was a mandatory first step! The egr jets (blocks) have tapered holes, so getting into each of them takes a little diligence.

Far better!

I just got back from Fuel Injector Corp in Livermore, CA. The injectors all had the same flow rate and also had an excellent pattern. Robert put 3 new o-rings on each injector. The flow rate that most peopel read about is 145 ml/min. But that’s only at full open. Mine were also checked at the equivalent of 3k rpm, with 43 psi fuel pressure. The seal that goes between the injector and the intake manifold had tiny cracks in it on the lip, at the very top of the seal. So I had to order them from Honda. They are a rare item so it was going to be 3 days. So I had them expedited and they will get here tomorrow for $12 more. The seals were only about $4 each. I could see reusing the old ones, but with 220k miles I am just not going to do this work twice. So the Insight sits for another day. I’ll go get them and the o-rings for the intake manifold in the morning. I may take the egr plate back out since it’s waiting for o-rings anyway and use some solvent and q-tips to polish up the passages a little more. Depends on how energetic I feel. We have plans tonight so I may not have time. Regardless the egr plate is clean and will help the Insight run far better when it’s finally back together!

The fuel injectors are out, and ready to go to Fuel Injection Corp in Livermore, CA in the morning. It’s about an hour drive. For $25 for each injector they will get flow tested, cleaned, and flow tested again. One guy on the InsightCentral forum had this done and his flow numbers between injectors vastly improved. Drivability was greatly improved too.

I decided it was finally time to take out the EGR plate and see how badly clogged it was. I wasn’t disappointed!!

In a couple of places the carbon cutoff all flow of egr gases. This will be a huge factor in the Insights drivability.

Look how high the carbon is piled up on the gasket. Combined with the carbon in the passages made this egr system inoperable.

Another completely plugged egr passage.

That crusty looking egr valve was from another Insight that a guy was parting out. The whole unit was bent. I straightened it in a machinists vice. The pintle was bent too. Now after the Insight is all back together I will swap between egr valves to see if there is any difference.

Just used this small screwdriver for most of the carbon removal and then a paper towel and carb cleaner to wipe of the the very smooth gasket surfaces. I didn’t want to use scotchbrite pads as it would scratch the surface up.

The engine to egr plate gasket part number for my 2002 Insight.

The gasket has sealer bonded to both sides. So reusing an old gasket won’t be as reliable as a new one.

Freshly tested, ultrasonically cleaned, and soda blasted injectors right from Fuel Injection Corp. All new o-rings too.

I have the gasket for the egr plate in hand, and the intake o-rings on order. I plan to take out and clean the egr plate as it has 220k miles. Here is a link for the egr plate procedure. Also the injectors are coming out and I’m driving them to a place to have them cleaned and flow tested while I wait, in the morning.

My theory on the clutch bucking/chattering, especially in reverse, is that the thrust bearing on the crankshaft gets worn particularly bad on this car. Whenever we are at a stop and the engine goes into auto stop, you have to have the clutch in for the car to restart. When the clutch pedal is pressed in, the crankshaft is pushed toward the other end of the motor. Since the oil pressure is zero, then there will be more wear on the thrust bearing of the motor, than normal.

My theory is based on the experience I had with an old Plymouth that I had replaced the clutch and pressure plate on. I had the flywheel surfaced. I dial indicated the flywheel, used new pilot and throwout bearings too. Still the clutch chattered. When I dial indicated the crankshaft end play it was about at max spec as I recall. Putting in a new thrust bearing completely cleared the clutch chatter up.

Granted, we have motor mounts that really need to be in good shape to keep our engines from chattering when the clutch is engaged, but starting up the motor so many times with the oil pressure at zero has to have a price. I’m aware that there is oil still present on the bearing and crank surfaces, but without pressure the thrust of the pressure plate, probably 10-20 lbs on this tiny car, pushes the crank journal snugly up against the thrust bearing. My Plymouth had a heavy duty pressure plate and it put 3000lbs of thrust on the clutch disk, divided by the leverage of 50-60, puts about 50-60 lbs of thrust directly on the crankshaft. So again, our Insights are a lot lighter duty, but I think the lack of oil pressure over the incredible amount of miles that these cars can last up to, supports my theory. The thrust washers are p/n 13331-679-003. 2pcs required. The two end seals for the oil pan are also needed, and a tube of sealer for the rest of the oil pan rail.