OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Victa Lawn Mower Frames Identify Victa Pro 550

What year would this Victa Professional 550 be?

The model number on the air filter is: WQ 197EX9

Is the motor the original fitment or an older retrofit?

There is no spark produced form the magneto even without the kill switch lead. The coil resistance is 9 ohm.

Are parts still available for this engine? If so, is there a parts list?

Does anyone know if the later c1990's victa power torque engine will fit the base?

LRT

Ps. How much compression should be expected with a Victa?

The engine spins over by hand easily and the compression stroke is barely distinguishable when spinning the flywheel by hand with the cover off. There is no compression rebound whatsoever.

Should be a decomp valve under the cover, I can't see the decomp tube coming up from the carby so anything is possible. Remove the cover, remove the decomp if it is there and put a spark plug in the hole and then see what compression is there

Hi Norm,

Thanks for your prompt reply.

Yes it does have a de-comp valve under the cover. I'll do what you suggest tomorrow & get back with the results.

When turning the engine over, it looks as though it has a bent crankshaft.

The owners description was it got harder & harder to start & then finally wouldn't start at all.

Caleb

those motors used a longer crank than a regular 18" engine, what makes you think the crank is bent?

When turning the engine over, the flywheel and centre of the shaft has a pronounced side to side wobble. There is no side play as if the bearings have worn.

I haven't had time to have a proper look at it yet though.

Caleb

fair enough, they are simple enough to strip and rebuild,
does the height of the blades vary on rotation ? ( from side to side )

No there isn't any noticeable height difference between the blades when they are rotated. Can you still get piston rings & the magneto from Victa?

G'day LRT, and a warm welcome to the ODK Forums.

From that model number, it's 86-87 year of manufacture; it's actually the 'Pro 550 Self Propelled' model. One of the very last of the full-crankshaft Victas; most of the model range had gone to the half-crankshaft PowerTorque engine by then. So it's the original engine I'd say, and no, a PowerTorque won't fit it.

Most parts are still available for this one, with the exception of the decompressor valve assembly. However, if that one has three clips holding the diaphragm chamber together, rebuild kits are available, e.g. HERE.

Piston rings are available in standard and three oversizes. That said, it's fairly rare for Victa 160's to get away with rings only when they're worn; the bores tend to wear oval, and they need to be rebored.

The basic service info on the engine and carby is available in the numbered sections HERE as free downloads; the lower 'Attachments' docos require a paid subscription for access.

This engine has electronic ignition; if it has the separate electronic module, the problem could lie in either the coil or the module.

Thanks Gadge,

Yes it does have a module that appears to have been replaced recently.

How to I test the module?

The coil resistance is 9 K Ohm.

Caleb

Try removing the coil from the body and clean where it attaches so that it gets a good earth and the module needs a good earth as well

Hi Norm,

I've cleaned all the contacts & checked for a good earth but there still isn't any spark. The module appears to be fairly new. Do the terminals on the coil have a polarity? The mower had been to several shops before I got the job so I don't know if things are connected up correctly.

Will a Victa MAO5617 universal module work?

http://www.gaspares.com.au/program/...20902102&GROUP=MW%20ELEC%20ECP%20VIC

Not sure if that module would work with the coil, probably would, but if you say the one you have looks fairly new I would think it is probably ok. Seeing you tested the coil I guess the plug lead is ok. Very annoying when you don't have boxes of bits to mix and match with to eliminate each component. Makes you wonder why it has been to several mower shops, I guess they figured it wasn't worth their time. Problem is once they start replacing bits the cost plus labor add up very quickly. Have you checked it for compression yet? I probably have a few of those motors kicking around here, quite a few I have never looked at so not really sure what is there, always happens when you pick up bulk mowers from ebay or gumtree. They just get pushed further back into the shed

There are basically two resistance readings for the coil; plug lead to earth or primary terminal, which should be 8.5-9.5 k ohm; and primary terminal to earth, which should read 0.2-0.5 ohms [if the meter will read that low].

The resistance across the module seems to measure around the 4.5 - 5.5 k ohm range.

The plug lead to primary or earth terminals: 9.0 k ohm

Between primary and earth terminals: 1 ohm

Between terminals on module: 4.5 k ohm

I purchased a NOS coil and it reads 8.5 k ohm on the plug lead to primary or earth. Otherwise it reads exactly the same as the current coil.

Does it matter which terminal is the earth or primary?


I haven't put the compression gauge on it yet, but it feels as though its got about 80 psi or so with the decompressor replaced with a spark plug.

Secondhand Victa's are virtually non-existent around here.

Caleb

Ok so dumb question what about the kill switch in the carby, pull the wire off that goes through the side first and the one through the rear second. You also need the throttle in the run position so you can pull the center wire out

Unfortunately Norm, both leads to the carby were out when I picked it up, so I don't know which goes where. There is no spark with the leads disconnected & isolated.

Just noticed both pins are different & can't be interchanged.