OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Viking MT433H ENGINE Replacenemt

I Have a 1999 Viking MT433H Ride on mower fitted with a briggs and stratton 13.5 hp engine. Unfortunately this engine has given up the ghost (ie no compression at all) and i am now looking for a replacement. I am unsure as whether or not i should go for a second hand engine or brand new. iF I go brand new i will stay with briggs and stratton. What engine would best fit this sort of mower? i am not interested in getting a chinese one. Would a briggs and stratton 13.5 hp intek be suitable for my viking or should i look else where.

Hi Coolrussy,

Yes the Intek engine will fit. I'm not sure if the bonnet will close though.

What is the model, type and code of existing engine?

Here is one with an Intek fitted.

Viking MT433H

The numbers are as follows
28T707
1121-E1
990518ZE

Hi Coolrussy,

The engine you need to replace the old one is a Briggs & Stratton Intek 219907-3026-G5.

This has the same crankshaft (Tapped 7/16-20 with keyway) as the old engine. However, it is still worth measuring the shaft before ordering the new engine just in case it is different, because there were some anomalies. What you may find with some re-powering jobs, is that the bonnet or side cowling may not fit over the new engine and may need modification.

REPLACEMENT ENGINE SPECS

SKU: 219907-3026-G5
Weight: 66 lbs.
Oil Capacity: 48 fl. oz.
Air Cleaner: AIR CLEANER, CARTRIDGE TYPE
Air Cleaner Cover: AIR CLNR COV COL 122 - AMERICAN RED
Chg System: ALTERNATOR, DUAL CIRCUIT
Bearings: BEARINGS, PLAIN PTO
Blower Housing: TEARDROP INSERT, 290 BLACK
Bore Size: 3.44
Stroke: 2.26
Intake: LOW VACUUM WITH PURGE PORT, CAPPED
Casing Clamps: CASING CLAMP & TORX SCREW, OPP CYL HEAD
Controls Groups: CONTROL GROUP 01, MODEL 17/21
Cylinder Head: CYLINDER, ALUMINUM W/C.I.SLEEVE
Deflectors: DEFLECTORS, SIDE OUT LOOSE
Dipsticks: DIPSTICK, OPPOSITE CARB SIDE
Oil Drain: OIL FILL, OPPOSITE CARB SIDE
Misc: FUEL HOSE, LOW PERM 3 IN W/40 MICRON FILTER
Flywheel: FLYWHEEL, LOW MASS EQUIP FOR ELEC START
Fuel System: FUEL SYSTEM, WITHOUT FUEL TANK
Governor: MECHANICAL GOVERNOR
Exhaust: MUFFLER, PERFORMANCE QUIET INSTALLED
Spark Plug: WIRING HARNESS ID = 393362
Starting System: STARTER, 12 VOLT REGULAR

Is the recommended engine a 13.5 hp

It is either 12.5 or 13.5 hp. There seems to be a discrepancy with this engine size.

I have a 28T707 Briggs & Stratton fitted to a 2002 Viking MT433T that has 12.5 hp on the cowl even though it is exactly the same model as your 13.5 hp engine.

That original engine (28T707-1121-E1) is rated at 13.0 Gross HP by Briggs spec sheet. Briggs Power Portal has the 219907-3026-G5 at 12.5 Gross HP. Briggs does list the one above as a direct replacement but I would very leery of it hp wise. I have seen 210000 series rated as low as 10.5 hp and they are gutless wonders at that rating.

Personally if I was replacing a 13.5 Hp L-head I go with the 310000 series rated at 15.5 Gross HP through I have seen them label anywhere from 15.5 to 17.5 Gross HP. I one rated at 15.5 hp on my 38 inch cut Bolens and one label at 16.5 hp on my Yard Machines 42 inch cut; same engine parts wise. The one on the Yard Machines is way under powered as need to slow to a crawl when cutting slight tall grass when compared to the Bolens that cut grass as tall as the hood if travel slowly. That is why I go to put a 21 gross hp on it this year if I going to keep it for my personal use; just to change engine pulley and belts size. I just look at why lose 7 cubic inches when I can go up 3 cubic inches.

Looks great on paper EPA wise as the 21 cu in does use less fuel. Something else to think about too that Gross HP is usually rated at 3600 rpms and both the 28 and 21 being talked about here are set at 3400 rpm max.

The new SAE J1940 standard requires all engines produced after and including October 1, 2013 must be within 95% of the declared rated power and torque as opposed to the old standard of 85%. SAE (Society of Automotive Engineers) has also stated that the engine manufacturer must disclose the rpm for rating and with the GROSS (SAEJ1995) or NET (SAEJ1349) horsepower.

This because of so much mis-info on the actual Gross HP over the years and the manufactures were even sued about it years ago. That they went with Ft-lb torque specs but I see they are creeping back to HP rating again. Still gives problems when replacing engines. So when replacing a pre 2013 engine go with 85% of the labelled Hp and compare to 95% of the new replacement engine and there is still no guarantee that you would have enough power; hence, why I usually up size the engine to next size whenever I can.

Thanks for the great information AVB. It will be a very helpful guide for me when I'm faced with repowering jobs. I appreciated your comments about engine horsepower ratings and your repowering experience.

Thank you for the ideas people but i am leaning towards the 13.5 hp intek as i do want the pull start however i am still confused about the shaft size would my old engine have a 1 inch shaft

The 28T707-1121-E1 had the following crankshaft. Don't have any info the new engine's crankshaft.

Yes the crankshaft fitted to the 219907-3026-G5 engine has the same dimensions. (crankshaft part no.: 591593)

The 2016 Briggs & Stratton Repower Engine Specifications guide now only shows a 10.5 & 11.5 HP 21 cubic inch engine. The next model up is the 31 cubic inch 17.5 HP.

See further the link below (page 15 onwards):

2016 Briggs & Stratton Repower Engine Specifications Guide

Also, have you had a look at why the current engine has lost compression? It may be as simple as a failed head gasket or a sticking valve.