ottawa-4hp serialtag

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Initial Story

This is my new toy... an Ottawa 4HP engine. I've learnt heaps about this engine since picking it up last weekend (April 6th 2002). I've found a manual online, received vast amounts of useful information from George and Helen Myers (The Ottawa People!) and Alan Bowen.

The information I've had so far amounts to:

  • It is a drag saw engine - the former owner aquired it as a drag saw, but disposed of the drag saw portion (bummer).
  • The second flywheel and pulley are not original - they were added to balance the engine. The second flywheel does appear to be an Ottawa flywheel.
  • The engine is kerosene with petrol/gasoline start
  • The cup on top of the hopper is a priming cup for starts
  • The engine was probably made around 1923 or so (according to George amp; Helen's best information)
  • Throttle governed
  • Definately not original exhaust

I've even received a Instruction and Parts book and have a kind offer from Alan Bowen to send another manual, and some other literature. - Thanks mate!

George and Helen Myers provided a wealth of useful information including some dating information:

This engine has to be 1923 or newer because of the EK mag. The 4hp was still being advertised in 1924. The serial numbers below TE3000 appear to have Wico PR mags originally.
Note that Richard Hunt (the fomer owner) felt that this engine was a 1917 vintage. There are some differences between it and the 1921 - 1928 manual I have, but mostly repairs which have been made during its life. The exhaust push rod is not original. The magneto trip push rod is not completely original.

Once again, the SEL has proved its community spirit by providing much useful and interesting information in just a few hours.

 

The engine is home now and running

running
When I picked up the engine, Richard and I did get it going, but it was very hard to start and did not want to keep running. I had a chance to play with the engine a couple of days after getting it home, and started checking it over to find out why it was hard to start. I found the following items which needed attention (this list reads like the list you get after one of those "free checkups" from a mechanic):
  • The magneto timing was out - the trip mechanism has four positions, no trip (safety or stop), start (fires right on TDC), run (fires a few degrees before TDC) and "notch 4" which is not explained in the manual and seems to be little different to three. It was only tripping half the time on start, and tripping late on run. I fixed it according to the manual.
  • The valve timing was slightly out, the inlet was open late
  • The butterfly valve in the carb was held almost closed even when the engine was stopped - I reset the lever on the valve and altered the length of the push rod so that the valve is open when the engine is stopped, and the rod has enough movement to fully close it when the engine is up to speed.
  • The conrod/crankshaft bearing was dry as a bone and heating up (good thing I stopped running after a couple of minutes). On investigation I found tree-bark and what appeared to be 80 year old grease in the grease cup. I've cleaned out all the cups and and refilled with white lithium grease. I have to check these cups out, they look like oil cups rather than grease cups.

I've replaced the exhaust with a straight pipe with holes drilled in it and a screw on cap. This seems to work reasonably well and is a slight concession to excess noise. To be original it would only have a short straight 1.25" pipe.

After doing everything above it runs on the second or third pull on the fly-wheels. I use the starting procedure from the manual rather than using the priming cup - seems to run pretty well now. It is running a little fast and I have some more work to do before it is shown, but I'm confident of getting it ready for Tulare 2002. I can certainly say that anyone exhibiting near me had better not be in direct line with my crank shaft or they're going to have an oil bath!

 

One thing about the engine I'm not sure if I should change or not... it has two fly-wheels, but should have only one - that bit is not so bad - it looks more balanced with two, and the second one is at least from a similar engine - there is also precedent, Ottawa did not make a dual fly-wheel 4hp. They did make a dual fly wheel 2 1/2hp, and a 4 hp which had a balance wheel (a smaller wheel than the main flywheel) to power a saw bench (actually the saw bench parts include the balance wheel, it still does not "belong" to the engine). The bad bit is that the second flywheel is not keyed to the shaft. Obviously I cannot show the engine in this condition. The former owner suggested just boring a hole through the fly-wheel and shaft and bolting it on. I don't like this idea much as the bolts could snap fairly easilly under the stress of engine firing. I think the only choice I have is to either remove the 2nd wheel, or have the shaft keyed by a machinist and fit a gib key. I might be able to use large diameter knurled set screws (eg. holo krome knurled locking screws) but I'm really not sure how they'd perform in this application.

All in all, I'm happy with my purchase.

The only other thing I wonder about... I live 1200 feet above Berkeley in CA just about at the top of Grizzly Peak and the exhaust faces out over the valley... I wonder how far away you can hear it in this formerley quiet neighbourhood?

ottawa
This pic by Richard Hunt and © Copyright Richard Hunt. This picture shows the exhaust stack which Richard made for the engine. While it looks nice, I'm trying to move back towards originality a little. Richard did a pretty good job restoring this engine to the state it is in now - thanks for trusting me with your "first" :)

 

Bad News

After test running the engine after making yet more modifications to the throttle and trip settings (I can make it go on the second pull now and keep going strongly) I noticed that the main bearing on the conrod was warm - alarming considering the engine had only been running four or five minutes - should be just about cold to the touch. I opened it up and discovered that the bearing half nearest the piston is broken - there was no damage to the conrod or the bearing surface of the crank shaft, but there is no way it can be run in this condition. It would soon destroy the crank, or worse sieze and destroy the engine. I was going to show this engine at Tulare CA this coming weekend, it will now have to be a static exhibit unless there is someone out there who sells these bearings and can get it to me in four business days. Alternately new babbit will have to be poured and I'm not equipped to do that. Anyone going to Tulare who could babbit for me at the show?

These pics clearly show the broken bearing half and the part of it actually stuck to the conrod - it is not wanting to come off despite some gentle levering.
broken bearing stuck


The back half of the bearing (away from the piston) is in fine shape - good enough for an engine not doing any work.


This is the engine running at the 2002 Tulare California show.

This picture was taken by

me and the ottawa at TulareDuring the Tulare 2002 show I met up with some of the SEL members who were instrumental in assisting me with getting the Ottawa up and running. Ron Haskell who supplied me with a "new" used conrod and bearings in much better shape than the originals on the engine. The Evans brothers Larry and Ken whose mobile tool shed made much of the job possible, and Kelley Garcia who offered knowledge of how her Ottawa was. Everyone from the WAPA club offered great encouragement throughout the work and came through with additional tools and the like when needed. A great club, if you live in California I recommend you seek them out. They are not your average club and every members cares for every other - always plenty of friendly people at their events.

I've made some modifications to the magneto detent rod to improve the timing dramatically.
I've been working on it again 07-Sep-2002... more bad news....
Today 08-Sep-2002 Disaster!
21 Sep 2002 She runs again!

July 2009 Sold... The Ottawa is off with a new family now.