46-07 & 47-13: Fitting Baffles to the Engine

In order to complete the SDS install on the engine, i needed to get the baffles attached, as the location for the baffle wiring connector on top of the engine needed to be worked out, as well as the location of the fuel distribution block etc. I repalced the rocker covers with the old chrome ones for the baffle fitment - to try and prevent them getting scratched.

For reference, the baffle kit i am using is the IO-360/390 baffle kit from Van's PN BAF-14-IO 360/390. "The RV-14 baffle kit is pre-cut and pre-punched and is a specific fit to the RV-14/14A. You may use it on the RV-14 with the angle-valve IO-360 or IO-390 engines.".

You can really see the kit improvements at Van's in the -14. I did a lot of reading about baffles, and there is a lot of wisdom which has been pre-built into these. For instance, at Cyl #2 and Cyl #3 many people install a washer to space the baffle away from the cylinders to improve airflow and cooling where the cylinder fins have no depth - in this kit, there is a little riveted on plate which does the same thing. 

Similarly, many people modify the baffle behind Cyl#3 for the same reason - most people hammer form a bulge, or build a little ramp to allow the air to flow - this kit already has that built in. 

I started with the aft left baffle, as i read online that this was one of the more difficult parts to fit. However, it worked our pretty well and went on with no major issues. There was a lot of marking areas where they were touching the case, removing, trimming and replacing; but i think that is just par for the course with baffles. 

The fit was pretty exceptional!

Next up was the aft right baffle. This also seemed to go on with no major issues. The little CB-31 steel plugs which fit up into the cylinder were a bit of a pain - i cross-threaded one when it rotated as i installed a bolt. The screw call-outs in the plans were also not correct for this engine - one screw was bottoming out against the cylinder. I ended up replacing these with AN3 bolts instead. 

Note in the image below you can see the build in cooling ramp to allow air to pass behind Cyl #3. 

The plans note that the Cyl #3 drainback tube should be disconnected - this was correct. You can't get the baffle in with it installed. You can undo the B-nut and just bend it slightly out of the way.

This spacer tube is slightly long here - i ended up trimming 1/32" off it later.

You really need to make sire that these barrel nuts are at the corrent angle and hand thread the screws into them to start, or you risk cross-threading them. I had to tap this one to fix the bothced threads.

I had to do surprisingly little filing around the rocker covers.

Next up was fitting the left and right forward baffles. These look a lot more trimming around the little curves of the case, bit overall the front right went on pretty easily.

The tube flange is for the cold air feed to the heat muffs (cabin heat). 

There were unfortunately a couple of scrapes - these were trimmed back. I will touchup the scrapes later on. 

They really fit surprisingly well!

The front left baffle was another story. The plans have you bolt the baffle to the normal place at the rocker cover, as well as to a small bracket on the top, centre of the engine. Underneath and inboard of the air filter frame, the baffles are supposed to bolt to 3 holes in the case:

What is drawn as the 'little screw' here, is a standard 1/4-20 screw (same as the rocker covers). The other 2 screws are massive 3/8-16 threaded behemoths! 

As you can see, i have the aft hole, but not the 2 massive 3/8 holes in the front of the case! 

Adapt and Overcome

My first issue was that i was unable to get a screw tight into the aft most hole (below). This was full of gunk, oil etc. Once we ran a tap into it, a standard 1/4-20 screw went in perfectly, and the top bracket was able to be fastened to the case. 

The bottom two holes were not going to line up with anything. I thought about drilling and tapping 3/8 into the case *for about a nano-second* then decided that was ridiculous. I needed to chop off the old bracket, and modify the baffle. 

Clearly my case is different from most IO-360's. 

I chopped off the old bracket.

Bent up a blank angle from some 0.032" scrap, then marked where the hole in the case would be and transferred this to the bracket.

Poor man's strap duplicator.

I then drilled the hole and trimmed the bracket to size. 

A hole pattern was laid out on the bracket, then it was match drilled to the baffle

It was cleaned, etched and primed then riveted to the baffle. 

I think this solution works well. 

That pretty much finished the fitting of the baffles, and will allow me to start installing all the SDS components onto the engine.