View Full Version : Dingo 420 Engine Removal Method

01-09-2008, 07:13 PM
Am removing the engine on a Dingo 420TX because compression is practically zero in the RH cylinder but normal in the LH. Probably time for a rebuild, but I'll know for sure when I tear it down after pulling it.

I'm getting bogged down in removing it, not sure what the easiest and quickest way is, and thought I'd throw out a question for those who've done this before. Learning the right way might save me a lot of time.

Do you pull the engine after removing the four mount bolts where the engine is bolted to the underneath plate? I tried loosening one but it spins like there is a nut on the bottom and I see no way to get underneath to get a wrench on it. Already the battery and box, fuel tank, and rear plate have been removed.

Or do you pull the entire under-engine plate off (looks like only four carriage bolts and nuts hold it to the side plates), remove it and the engine as an assembly, and then remove the four engine mounting bolts after they are easier to get to? Doing it this way seems to mean almost all the hydraulic lines would need to be removed first so the plate could come out, something I'm trying to avoid.

Thanks in advance.

- Richard


01-09-2008, 08:02 PM
first the undercarriage now the engine!!! you cant catch a break. how many hours on that machine?

01-09-2008, 10:30 PM
By the looks of the below pic, If you can't get a wrench between the two plates it will have to come too.

If this is the Kohler I think I'd pull the valve cover and check for a loose/bent push-rod first.

Also, If you do end up pulling the plate with the engine I'd stick some shorter screws through the engine mount holes and tack weld the nuts on the bottom for the next engine removal.


Good Luck

01-10-2008, 02:17 AM
Picasso, it was a package deal including five attachments for only a little more total than a used bare 420 Dingo typically runs, so buying was a no-brainer, as everyone knows Dingo attachments are the true plums. Knew the engine had problems (so did seller and I bargained him down) and figured even if I had to repower with a new Kohler and do some other work it would still be a great deal. 870 hours and mostly not bashed, cobbled or idiot-rigged. Hydraulics all work fine. Seller had Toro service for the most part. Recent new tracks.

Restrorob, thanks for the info -sorta jives with what I was fearing about being a major pain to pull the engine.

The plug in the bad cylinder was mucked up solid so I'm naturally thinking valve problems or broken rings. Leakdown test seems to point to bad exhaust valve. Pushrods seem straight, but what's weird is there's no lash in the rockers arms at TDC. I thought pulling that RH cylinder head would be easier if the engine were removed first, but now I'm reconsidering. May pull it in place to figure out what's going on. At the very least, a lot of deposits will need to be cleared out of the head.


- Richard



01-10-2008, 01:31 PM
The plug in the bad cylinder was mucked up solid so I'm naturally thinking valve problems or broken rings.


These engines are know for blowing head gaskets mostly at the oil return port, This lets the cylinder suck oil in and foul the spark plug as you described.

Also this engine will have no valve lash due to the hydraulic lifters.

If you can weasel the head off that would probably save a lot of time.

In some cases you can't see a full blown out area, But so far with your explanation this sounds like the classic blown head gasket.

Good Luck

01-10-2008, 10:10 PM
We recently replaced an engine on a Dingo and I think the book time was over 10 hours.

We have a Heftee lift plus a fork lift so jobs like this aren't much of a problem but working off the ground would be tough.

This will be a good time to replace worn rollers and to change the hydraulic oil & filter.

Send me a pm if you need any advice.


01-10-2008, 11:15 PM
This afternoon I disassembled more of the Dingo to where I could pull the head off with the engine in place. Found a burned exhaust valve, with a small chunk missing along the edge. And from what Restrorob said, I'm suspecting a blown head gasket also, although that wasn't obvious.

I'll probably pull the other head too as long as this much is disassembled, check it out, and hopefully will get off easy this time without needing a complete rebuild or new engine. Bore looks great.

Yeah, Oldtimer, as long as it's down rollers are getting replaced (see my other posting about the improved solid steel Dingo rollers), the hyd fluid and filter changed, and a bunch of minor repairs and adjustments getting done.

Thanks for everyone's advice - you definitely saved me some time and helped me out here.

- Richard



01-11-2008, 12:13 AM
When you go down to get your parts make sure you get the complete head gasket KIT. You will need a KIT for each side of the engine, The kit comes with new head bolts that should be replaced as well so don't let them sell you gaskets only.

01-11-2008, 01:32 AM
Restrorob, if you're old like me and remember "valve grind sets" , this is exactly what I was wondering was available for the Kohler and you just answered my unasked question. I've also downloaded the service manual from Kohler so knew new head bolts are needed.

Is retorquing the head bolts after a few hours use necessary with these small engines?

Thanks again.

- Richard

01-11-2008, 08:03 AM
if you're old like me and remember "valve grind sets"

Well....I'll just say, I've been spinning wrenches over 30 yrs. So yeah I remember the Ole valve grind sets. I have never had any problems with not re-torquing these small engines.

01-11-2008, 10:54 AM
hello, Using a dedicated head gasket spray/adhesive works wonders in a compromised head gasket situation .The brand HYLOMAR i have used since first starting my original trade . Many years ago !!
The spray fixed Fords really well ,the situation of oil weeping head gaskets solved [included a cylinder head face /grind ]

On the kohler the issues are
1/ there is no fire ring [steel ring that protects the edge of the gasket from the combustion process ] Gasket therefore degrades , not really an issue in reality except when u have a oil drain gallery so close .

2/ there is no additional sealing provided around the oil passage typically a raised sealant bead as per auto gaskets .

3/ the head gaskets are not 100% perfect fit to the combustion chamber in the cyl head [the combustion chamber is slightly bigger] therfore the combustion process eats the gasket . Does this have much to do with the kohlers running on after turning the engine is turned off . Thats another story ...


01-11-2008, 11:00 PM
tomo, I can't seem to find HYLOMAR stocked locally. Permatex used to distribute it, but no longer. Most auto parts store clerks have never heard of it, and it's only in the hot rod and racing shops where they know what it is, but so far I haven't run across a place that stocks it. The HYLOMAR web site mentions the blue paste, but not aerosol cans.

Any suggestions where to get the aerosol cans?


- Richard

01-13-2008, 05:07 PM
made in Germany under the licence of HYLOMAR LTD.


part number for 400gram can is MPL.Y400 hylomar spray


PS PS very very good product ,cannot recomend it enough

01-13-2008, 06:11 PM
hello ,
yes hard to find in the usa but after all the s***t i found it .

Permatex Hylomar aerosol high temp gasket dressing


Permatex Hylomar copper high temp spray a gasket and high temp adhesive sealant


01-13-2008, 06:27 PM
hello, the particular one i use sprays blue in colour
The company has changed ownership and distributors in the usa and together with that the product is renamed4 us market ,no wonder it was hard to find !!!!!!


01-13-2008, 10:47 PM
Hi tomo,

I finally tracked some Unversal Blue down. A friend has a half-full tube which he offered to loan me. And on the net I tracked down a US source where I can order aerosol cans.

But it is REALLY difficult to find it sold at retail stores locally. A few years ago, when Permatex was distributing it, apparently Hylomar was readily available even at major consumer chains like Pep Boys, Kragen and Autozone. But not today. I also asked several NAPA stores, a few speed and racing shops, and industrial supply companies, with no luck. Guys had often heard of the stuff, but didn't stock it.

By the way, since I see you are in AU, did you know that in America the old school auto parts stores which have a parts counter stretching the length of the store manned by seasoned pros (who might well wrench on a race car in their off hours) are fast disappearing in favor of the "supermarket" chain stores which feature large shopping aisles full of mostly consumer stuff and a small parts counter shelving only the most popular basic parts. The person who waits on you is apt to be young and not have much practical knowledge about parts. As opposed to the old stores, where if you ask for a ring gear for say a "19xx" Plymouth Belvedere, they will immediately ask without consulting a parts manual, "What size bolt, 3/8" or 7/16?". Not to totally put down Autozones or Kragens, as I've had some good experiences there dealing with helpful, knowledgeable staffers tracking down obscure parts, but that is just the general trend in America these days.

Thanks again for the tip, toma. I've taken your advice and won't be buttoning the Kohler back up again until I get some Hylomar.

- Richard

01-14-2008, 07:24 AM
Rick, can you tell us the distributor where you tracked down the aerosol cans since they seem so difficult to find. Thank you


01-14-2008, 10:01 AM
870 hours, what happened to it? i replaced my dingo engine at 2548 hours. same thing though, the right side was gone and the left side was still ok. mine is a tire model and very easy to swap the engine.

01-14-2008, 01:05 PM

Type Hylomax into the product search field.

Paolaken, I bought used with a known bad engine.

By the way, I pulled the LH head off this weekend and although it showed 100 PSI on a compression gauge and good on a leakdown test, the head gasket was just starting to leak in the same spot where the RH head gasket blew out. Valves were good, though.

- Richard

01-14-2008, 03:12 PM
Rich, I tried typing Hylomax into the product search engine and it came up with no matches. Is there another name or manufacturer?


01-14-2008, 03:43 PM
hello, thru the power of the people we finally found it ah ah :rolleyes:

type in Hylomar into the search engine on BSR products page not hylomax


01-14-2008, 04:36 PM
Tomo-thanks. I found it


01-14-2008, 05:45 PM
Sorry, I had a brain fart. (Not infrequent with me!) :dizzy: Of course it's "Hylomar" and not "Hylomax".

Thanks for correcting me, tomo!

- Richard

02-02-2008, 01:36 AM
Got my Dingo back together and running. Want to thank everyone who responded to my original question. Some very useful information was provided which helped me out considerably.

Found one badly burned exhaust valve and a blown head gasket. Also replaced the head gasket and exhaust valve on the other cylinder as long as I had the unit torn down anyway. Looked like that gasket was leaking slightly also, so it was fortunate I pulled that head to check.

Thanks again, especially to Restrorob and tomo, your help was much appreciated.

- Richard

02-02-2008, 11:41 AM
Anytime Richard, Glad to hear she's back up and running !

02-02-2008, 04:19 PM
Happy to help Richard .