# Holt 4 cyl head question



## Capt,n John (Apr 13, 2015)

The Holt engine I got, the cylinder has a "open spot" in the intake runner. Is this a big problem, as I would think the head gasket would seal things up.? I will try to post a photo. Thanks John








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## johnnyo (Apr 13, 2015)

Hi John
I think I'm seeing an intersection of you're intake port and a head stud hole. If correct I had a similar situation on my Holt and found it didn't matter in performance as nut at top and flat sealing surface on bottom blocked it off.These heads did require careful drilling as I noted there's not much room for those holes. Hope this helps, if you need to seal it try a little high temp RTV.
Goodluck


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## Capt,n John (Apr 13, 2015)

Thanks for the reply. I hope with a good head Gasket & some hi temp RTV it may work out ok.  I hope.  :wall:   Best Regards, John


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## gbritnell (Apr 14, 2015)

Hi John,
I may be mistaken but it sure looks like the port diameter is too big.
gbritnell


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## Capt,n John (Apr 14, 2015)

The port dia is 5/16 like the print calls for. Its the angle that was off, some ports where drilled better as the angle was closer to what it should have been. I agree the ports are drilled too big & the guy that drew up the prints should have designed the ports a tad smaller. My opinion  is, a low speed engine does not need as big of port runners.  I did talk with a guy on another forum that his Holt  engine had the same problem, with the head bolt hole & the ports open to each other.  The heads came already done so I got to make them work somehow.  Best Regards,  John    :wall:


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## Krinos (Feb 3, 2018)

I received a Holt four-cylinder engine from a friend's deceased father, but do not have the instructions for it. Does the engine below look like yours? If so, do you know where I can find instructions for it? I can't find anything about it online. Here is a link to a video of an engine that looks exactly like the one I have.
[ame]https://www.youtube.com/watch?v=AjQLKLaDOTY[/ame]


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## gbritnell (Feb 3, 2018)

When you say that you received it do you mean as a kit or finished? What kind of instructions are you looking for? Do you want to know how to run the engine?
gbritnell


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## Krinos (Feb 4, 2018)

I received it in a cardboard box, about 40-50% assembled. I know my way around engines and had it completed in a few hours, but it is missing two piston rings for cylinder one. Do you know where I can find replacement parts? I also would like to know what kind of oil and fuel it takes, and how much?
Thank you! -Krinos


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## johnnyo (Feb 5, 2018)

I used 1" Dia. rings purchased from a vendor at the Cabin Fever Expo. I forget the name but they sold ignition parts like rings, plugs, wires and caps. I made a set of rings for another engine I'm working on from info off the internet. You may want to check the piston to see what dimensions were used in it for the rings. I wouldn't try removing the others as they break easy. I use a 5w- 10w synthetic oil in mine as it helps dissapate heat a little better then conventional oil. I fill it to the split in one of the connecting rods with the rod in the lowest position (BDC). 
If I think of vender name I'll throw it on here. For fuel I used both Coleman fuel and airplane fuel (100 LL). Old Coleman fuel would cause running issues so use a fresh can. The 100LL fired it right up after trying an old batch of Coleman.
Hope this helps.
Johnny O


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## gbritnell (Feb 5, 2018)

Debolt Machine in Zanesville, Ohio has 1.00 dia. rings. Hopefully it was bored to that exact size.
As far as fuel and oil I use regular unleaded gasoline and 30wt. detergent oil in my Holt engine.
gbritnell


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